Benzochromene derivatives

ABSTRACT

The present invention relates to benzochromene derivatives of the formula I  
                 
in which the various parameters are as defined in the text, and to liquid-crystal media which comprise these compounds, and to the use of the media in electro-optical displays, in particular in VAN LCDs.

The present invention relates to benzochromene derivatives, preferably mesogenic benzochromene derivatives, in particular liquid-crystalline benzochromene derivatives, and to liquid-crystalline media comprising these benzochromene derivatives. The present invention furthermore relates to liquid-crystal displays, in particular liquid-crystal displays addressed by means of an active matrix (AMDs or AM LCDs (“active matrix addressed liquid crystal displays”)) and very particularly so-called VAN (“vertically aligned nematic”) liquid-crystal displays, an embodiment of ECB (“electrically controlled birefringence”) liquid-crystal displays, in which nematic liquid crystals of negative dielectric anisotropy (Δε) are used.

In liquid-crystal displays of this type, the liquid crystals are used as dielectrics whose optical properties change reversibly on application of an electric voltage. Electro-optical displays which use liquid crystals as media are known to the person skilled in the art. These liquid-crystal displays use various electro-optical effects. The most common of these are the TN (“twisted nematic”) effect, with a homogeneous, virtually planar initial alignment of the liquid-crystal director and a nematic structure twisted by about 90°, the STN (“supertwisted nematic”) effect and the SBE (“super-twisted birefringence effect”) effect, with a nematic structure twisted by 180° or more. In these and similar electro-optical effects, liquid-crystalline media of positive dielectric anisotropy (As) are used.

Besides the said electro-optical effects, which require liquid-crystal media of positive dielectric anisotropy, there are other electro-optical effects which use liquid-crystal media of negative dielectric anisotropy, such as, for example, the ECB effect and its sub-forms DAP (“deformation of aligned phases”), VAN and CSH (“colour super homeotropics”).

An electro-optical effect having excellent, low, viewing-angle dependence of the contrast uses axially symmetric micropixels (ASMs). In this effect, the liquid crystal in each pixel is surrounded cylindrically by a polymer material. This mode is particularly suitable for combination with addressing through plasma channels. Thus, in particular, large-area PA (“plasma addressed”) LCDs having good viewing-angle dependence of the contrast can be achieved.

The IPS (“in plane switching”) effect, which has been increasingly employed recently, can use both dielectrically positive and dielectrically negative liquid-crystal media, similar to guest/host displays, which are able to employ dyes either in dielectrically positive or in dielectrically negative media, depending on the display mode used.

Since the operating voltage in liquid-crystal displays in general, i.e. including in displays based on these effects, should be as low as possible, use is made of liquid-crystal media having a large absolute value of the dielectric anisotropy, which generally predominantly and usually even very substantially consist of liquid-crystal compounds having a dielectric anisotropy having the corresponding sign, i.e. consist of compounds of positive dielectric anisotropy in the case of dielectrically positive media and of compounds of negative dielectric anisotropy in the case of dielectrically negative media. In the respective types of media (dielectrically positive or dielectrically negative), at most significant amounts of dielectrically neutral liquid-crystal compounds are typically employed. Liquid-crystal compounds having the sign of the dielectric anisotropy opposite to the dielectric anisotropy of the medium are generally employed in extremely small amounts, or not at all.

An exception here is formed by liquid-crystalline media for MIM (“metal-insulator-metal”) displays (Simmons, J. G., Phys. Rev. 155 No. 3, pp. 657-660 and Niwa, J. G. et al., SID 84 Digest, pp. 304-307, June 1984), in which the liquid-crystal media are addressed by means of an active matrix of thin-film transistors. In this type of addressing, which utilises the non-linear characteristic line of diode switching, it is not possible, in contrast to TFT displays, to charge a storage capacitor together with the electrodes of the liquid-crystal display elements (pixels). A reduction in the effect of voltage drop during the addressing cycle therefore requires the highest possible base value of the dielectric constant. In dielectrically positive media, as employed, for example, in MIM-TN displays, the dielectric constant perpendicular to the molecular axis (ε₁₉₅ ) must therefore be as large as possible, since it determines the base capacitance of the pixel. To this end, as described, for example, in WO 93/01253, EP 0 663 502 and DE 195 21 483, compounds of negative dielectric anisotropy are simultaneously employed in addition to dielectrically positive compounds in the dielectrically positive liquid-crystal media.

A further exception is formed by STN displays in which, for example in accordance with DE 41 00 287, dielectrically positive liquid-crystal media comprising dielectrically negative liquid-crystal compounds are employed in order to increase the steepness of the electro-optical characteristic line.

The pixels of the liquid-crystal displays can be addressed directly, time-sequentially, i.e. in time multiplex mode, or by means of a matrix of active elements having nonlinear electric characteristic lines.

The most common AMDs to date use discrete active electronic switching elements, such as, for example, three-pole switching elements, such as MOS (“metal oxide silicon”) transistors or thin-film transistors (TFTs) or varistors or 2-pole switching elements, such as, for example, MIM (“metal insulator metal”) diodes, ring diodes or back-to-back diodes. In TFTs, various semiconductor materials, predominantly silicon, but also cadmium selenide, are used. In particular, amorphous silicon or polycrystalline silicon is used.

In accordance with the present application, preference is given to liquid-crystal displays having an electric field perpendicular to the liquid-crystal layer and liquid-crystal media of negative dielectric anisotropy (Δε<0). In these displays, the edge alignment of the liquid crystals is homeotropic. In the fully switched-through state, i.e. on application of a correspondingly high electric voltage, the liquid-crystal director is aligned parallel to the layer plane.

Cyclic lactones of the formula

-   -   in which     -   —X—Y— is —CO—O— or —O—CO—         are disclosed in JP 2001-026 587 (A). These compounds are         characterised by broad smectic phases and are proposed for use         in ferroelectric liquid-crystal mixtures in JP 2001-026 587 (A).

U.S. Pat. No. 5,648,021 discloses fluorinated phenanthrenes of the formula

and fluorinated 9,1 0-dihydrophenanthrenes of the formula

These also have broad smectic phases and are likewise proposed for use in ferroelectric liquid-crystal mixtures.

DE 100 64 995 presents fluorinated phenanthrenes of the formula

-   -   in which     -   L¹ and L² are each, independently of one another, H or F,

and proposes them for use in nematic liquid-crystal mixtures, in particular for ECB displays. The example compounds in which L¹ and L² are both H and which contain one alkyl end group and one alkoxy end group have an only slightly negative Δε, whereas the example compounds in which L¹ and L² are both F and which contain one alkoxy end group, although having a more negative Δε, generally have greater rotational viscosity, significantly lower solubility and in addition in most cases inadequate UV stability.

It is thus evident that there is both a demand for further mesogenic compounds and also, in particular, a demand for liquid-crystal media of negative dielectric anisotropy having a large absolute value of the dielectric anisotropy, a value of the optical anisotropy (Δn) corresponding to the particular application, a broad nematic phase, good stability to UV, heat and electric voltage and low rotational viscosity.

This is achieved through the use of the mesogenic compounds of the formula I according to the invention

-   -   in which     -   Y is —CO—, —CS—, —CH₂—, —CF₂— or —CHF—, preferably —CF₂—,     -   L¹ and L² are each, independently of one another, H, F, Cl or         —CN, preferably H or F, preferably at least one of L¹ and L² is         F, particularly preferably L¹ and L² are both F,         are each, independently of one another, and, if present more         than once, also independently of one another,     -   (a) a trans-1,4-cyclohexylene radical, in which, in addition,         one or two non-adjacent CH₂ groups may be replaced by —O— and/or         —S—,     -   (b) a 1,4-cyclohexenylene radical,     -   (c) a 1,4-phenylene radical, in which, in addition, one or two         non-adjacent CH groups may be replaced by N, or     -   (d) a radical selected from the group consisting of         1,4-bicyclo-[2.2.2]octylene, 1,3-bicyclo[1.1.1]pentylene,         spiro[3.3]-heptane-2,4-diyl, piperidine-1,4-diyl,         naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl and         1,2,3,4-tetrahydro-naphthalene-2,6-diyl,     -   preferably     -   R¹ and R² are each, independently of one another, H, halogen,         —CN, —SCN, —SF₅, —CF₃, —CHF₂, —CH₂F, —OCF₃, —OCHF₂, or an alkyl         group having from 1 to 15 carbon atoms which is monosubstituted         by CN or CF₃ or at least monosubstituted by halogen and in         which, in addition, one or more CH₂ groups may each,         independently of one another, be replaced by —O—, —S—, —CH=CH—,         —CF=CF—, —CF═CH—, —CH═CF—,         —CO—, —CO—O—, —O—CO— or —O—CO—O— in such a way that neither O         nor S atoms are linked directly to one another,     -   preferably one of     -   R¹ and R² is alkyl or alkoxy having from 1 to 12 carbon atoms,         alkoxyalkyl, alkenyl or alkenyloxy having from 2 to 12 carbon         atoms and the other, independently of the first, is likewise         alkyl or alkoxy having from 1 to 12 carbon atoms, alkoxyalkyl,         alkenyl or alkenyloxy having from 2 to 12 carbon atoms or         alternatively F, Cl, Br, —CN, —SCN, —SF₅, —CF₃, —CHF₂, —CH₂F,         —OCF₃ or —OCHF₂,     -   Z¹ and Z² are each, independently of one another, —CH₂—CH₂—,         —CF₂—CF₂—, —CF₂—CH₂—, —CH₂—CF₂—, —CH=CH—, —CF═CF—, —CF=CH—,         —CH═CF—, —C≡C—, —COO—, —OCO—, —CH₂O—, —OCH₂—, —CF₂O—, —OCF₂—, or         a combination of two of these groups, where no two 0 atoms are         bonded to one another,     -   preferably —(CH₂)₄—, —CH₂—CH₂—, —CF₂—CF₂—, —CH═CH—, —CF═CF—,         —C≡C—, —CH₂O—, —CF₂O— or a single bond, particularly preferably         —CH₂O—, —CH₂—CH₂—, —CF₂—CF₂—, —CF═CF—, —CF₂O— or a single bond,         and     -   n and m are each 0, 1 or 2, where     -   n+m is 0, 1, 2 or 3, preferably 0, 1 or 2, particularly         preferably 0 or 1,     -   with the proviso that, if Y is —CO—, at least one of L¹ and L²         is not H.

Particular preference is given to liquid-crystal compounds of the formula I of the sub-formulae 1-1 to 1-3

in which the parameters are as defined above under the formula I, and

-   -   L¹ and L² are preferably both F.

Preference is given to compounds of the formula 1, preferably selected from the group consisting of the compounds of the formulae I-1 to I-3, in which

the sum n+m is 0 or 1, preferably 0.

A preferred embodiment is represented by the compounds of the formula I in which the sum n+m is 1 and preferably

m or n is,

Z² is preferably —(CH₂)₄—, —CH₂—CH₂—, —CF₂—CF₂—, —CH═CH—, —CF═CF—, —C≡C—, —O—CH₂—, —O—CF₂— or a single bond, particularly preferably —O—CH₂—, —CH₂—CH₂—, —CF₂—CF₂—, —CF═CF—, —O—CF₂— or a single bond,

and L¹, L², R¹ and R² are as defined above under the formula I, and L¹ and L² are preferably both F.

Particular preference is given to compounds of the formula I, preferably selected from the group consisting of the compounds of the formulae I-1 to I-3, in which

n and m are both 0, and

L¹, L², R¹ and R² are as defined above under the corresponding formula, and L¹ and L² are preferably both F.

Compounds of the formula I containing branched wing groups R¹ and/or R² may occasionally be of importance owing to better solubility in the usual liquid-crystalline base materials, but in particular as chiral dopants if they are optically active. Smectic compounds of this type are suitable as components of ferroelectric materials. Compounds of the formula I having S_(A) phases are suitable, for example, for thermally addressed displays.

If R¹ and/or R² is an alkyl radical and/or an alkoxy radical, this may be straight-chain or branched. It is preferably straight-chain, has 2, 3, 4, 5, 6 or 7 carbon atoms and accordingly is preferably ethyl, propyl, butyl, pentyl, hexyl, heptyl, ethoxy, propoxy, butoxy, pentoxy, hexyloxy or heptyloxy, furthermore methyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetra-decyl, pentadecyl, methoxy, octyloxy, nonyloxy, decyloxy, undecyloxy, dodecyloxy, tridecyloxy or tetradecyloxy.

Oxaalkyl or alkoxyalkyl is preferably straight-chain 2-oxapropyl (=methoxy-methyl), 2-(=ethoxymethyl) or 3-oxabutyl (=2-methoxyethyl), 2-, 3- or 4-oxapentyl, 2-, 3-, 4- or 5-oxahexyl, 2-, 3-, 4-, 5- or 6-oxaheptyl, 2-, 3-, 4-, 5-, 6- or 7-oxaoctyl, 2-, 3-, 4-, 5-, 6-, 7- or 8-oxanonyl, or 2-, 3-, 4-, 5-, 6-, 7-, 8- or 9-oxadecyl.

If R¹ and/or R² is an alkyl radical in which one CH₂ group has been replaced by —CH═CH—, this may be straight-chain or branched. It is preferably straight-chain and has from 2 to 10 carbon atoms. Accordingly, it is in particular vinyl, prop-1- or -2-enyl, but-1-, -2- or -3-enyl, pent-1-, -2-, -3- or -4-enyl, hex-1-, -2-, -3-, -4- or-5-enyl, hept-1-, -2-, -3-, -4-, -5-or -6-enyl, oct-1-, -2-, -3-, -4-, -5-, -6- or -7-enyl, non-1-, -2-, -3-, -4-, -5-, -6-, -7- or -8-enyl, or dec-1-, -2-, -3-, -4-, -5-, -6-, -7-, -8- or -9-enyl.

If R¹ and/or R² is an alkyl radical in which one CH₂ group has been replaced by —O— and one has been replaced by —CO—, these are preferably adjacent. These thus contain an acyloxy group —CO—O— or an oxycarbonyl group —O—CO—. These are preferably straight-chain and have from 2 to 6 carbon atoms. Accordingly, they are in particular acetoxy, propionyloxy, butyryloxy, pentanoyloxy, hexanoyloxy, acetoxymethyl, propionyloxymethyl, butyryloxymethyl, pentanoyloxymethyl, 2-acetoxyethyl, 2-propionyloxyethyl, 2-butyryloxyethyl, 3-acetoxypropyl, 3-propionyloxypropyl, 4-acetoxybutyl, methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, butoxycarbonyl, pentoxycarbonyl, methoxycarbonylmethyl, ethoxycarbonylmethyl, propoxycarbonylmethyl, butoxyca rbonylmethyl, 2-(methoxyca rbonyl)ethyl, 2-(ethoxycarbonyl)ethyl, 2-(propoxycarbonyl)ethyl, 3-(methoxycarbonyl)propyl, 3-(ethoxycarbonyl)propyl or 4-(methoxycarbonyl)butyl.

If R¹ and/or R² is an alkyl radical in which one CH₂ group has been replaced by unsubstituted or substituted —CH═CH— and an adjacent CH₂ group has been replaced by CO or CO—O or O—CO, this may be straight-chain or branched. It is preferably straight-chain and has from 4 to 13 carbon atoms. Accordingly, it is in particular acryloyloxymethyl, 2-acryl-oyloxyethyl, 3-acryloyloxypropyl, 4-acryloyloxybutyl, 5-acryloyloxypentyl, 6-acryloyloxyhexyl, 7-acryloyloxyheptyl, 8-acryloyloxyoctyl, 9-acryloyloxy-nonyl, 10-acryloyloxydecyl, methacryloyloxymethyl, 2-methacryloyloxyethyl, 3-methacryloyloxypropyl, 4-methacryloyloxybutyl, 5-methacryloyloxypentyl, 6-methacryloyloxyhexyl, 7-methacryloyloxyheptyl, 8-methacryloyloxyoctyl or 9-methacryloyloxynonyl.

-   -   If R¹ and/or R² is an alkyl or alkenyl radical which is         monosubstituted by CN or CF₃, this radical is preferably         straight-chain. The substitution by CN or CF₃ is in any desired         position.

If R¹ and/or R² is an alkyl or alkenyl radical which is at least monosubstituted by halogen, this radical is preferably straight-chain, and halogen is preferably F or Cl. In the case of polysubstitution, halogen is preferably F. The resultant radicals also include perfluorinated radicals. In the case of monosubstitution, the fluorine or chlorine substituent may be in any desired position, but is preferably in the o-position.

Branched groups generally contain not more than one chain branch. Preferred branched radicals R¹ are isopropyl, 2-butyl (=1-methylpropyl), isobutyl (=2-methylpropyl), 2-methylbutyl, isopentyl (=3-methylbutyl), 2-methylpentyl, 3-methylpentyl, 2-ethylhexyl, 2-propylpentyl, isopropoxy, 2-methylpropoxy, 2-methylbutoxy, 3-methylbutoxy, 2-methylpentoxy, 3-methylpentoxy, 2-ethylhexyloxy, 1-methylhexyloxy and 1-methyl-heptyloxy.

If R¹ and/or R² is an alkyl radical in which two or more CH₂ groups have been replaced by —O— and/or —CO—O—, this may be straight-chain or branched. It is preferably branched and has from 3 to 12 carbon atoms. Accordingly, it is in particular biscarboxymethyl, 2,2-biscarboxyethyl, 3,3-biscarboxypropyl, 4,4-biscarboxybutyl, 5,5-biscarboxypentyl, 6,6-bis-carboxyhexyl, 7,7-biscarboxyheptyl, 8,8-b isca rboxyoctyl, 9,9-biscarboxy-nonyl, 10,10-biscarboxydecyl, bis(methoxycarbonyl)methyl, 2,2-bis-(methoxycarbonyl)ethyl, 3,3-bis(methoxycarbonyl)propyl, 4,4-bis(methoxy-carbonyl)butyl, 5,5-bis(methoxycarbonyl)pentyl, 6,6-bis(methoxycarbonyl)-hexyl, 7,7-bis(methoxycarbonyl)heptyl, 8,8-bis(methoxycarbonyl)octyl, bis(ethoxycarbonyl)methyl, 2,2-bis(ethoxycarbonyl)ethyl, 3,3-bis(ethoxy-carbonyl)propyl, 4,4-bis(ethoxycarbonyl)butyl or 5,5-bis(ethoxycarbonyl)-hexyl.

Particular preference is given to compounds of the formula I in which n=0 or 1 and m=0 and R¹ is methyl, ethyl, propyl, butyl, pentyl, vinyl, 1E-propenyl, 1E-butenyl or 1E-pentenyl, and to media comprising these compounds. Of these compounds, the alkyl-substituted compounds are particularly preferably employed.

The compounds of the formula I are prepared in accordance with the following schemes (Schemes I to XX).

The cyclic lactones can be prepared in accordance with Scheme I by intramolecular cyclisation of aryl phenyl esters which have been halogenated in a suitable manner by coupling reactions of the Ullmann type (Houben Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], New York, 1993). They can alternatively be obtained by palladium-catalysed intramolecular cross-coupling reactions as shown in Scheme II and Scheme III.

Alternatively, the cross-coupling can also be carried out in a first step with the correspondingly protected phenols and carboxylic acid esters, as shown in Scheme IIIa using the example of a Negishi reaction (Negishi, E. et al., J. Org. Chem. (1977) 42, pp. 1821-1823).

in which, as in Schemes Ia to Id, II, III, IIIa, IV to XX, unless explicitly stated otherwise,

R and R′ are each, independently of one another, as defined above for

-   -   under the formula I, and

Hal is halogen, preferably Br or 1.

A: Hasan, I. et al., Chem. Rev. (2002), 102, pp. 1359-1469,

B: Hennings, D. D. et al., Org. Lett. (1999), 1, pp. 1205-1208.

The ester precursors are synthesised by standard reactions (Houben-Weyl) from commercially available 4-bromo-3-fluoro-1-iodobenzene or (in the case where R=methyl from 4-bromo-2-fluorotoluene, or from 4-bromo-2-fluorophenol (ABCR, Karlsruhe, Germany)).

Alkyl side chains are advantageously introduced into the precursors by Sonogashira coupling as shown in Scheme Ia.

Precursors containing alkoxy side chains are advantageously obtained in accordance with Scheme Ib.

The two types of intermediate obtained in accordance with Scheme Ia or Ib can, as shown in Scheme Ic by way of example for the alkyl compounds, be converted either into the phenol or into the carboxylic acid and subsequently esterified.

The bromophenol can be protected and converted into the boronic acid in accordance with Scheme Id for subsequent Suzuki couplings.

C: Bringmann, G. et al., Org. Synth. (2002), 79, pp. 72-83.

D: Alo, B. I. et al., J. Org. Chem. (1991), 56, pp. 3763-3768.

The lactones (Ia) can, as shown in Scheme IV, be converted, analogously to EP 1 061 113, into the benzochromenes (1b) or alternatively, using Lawesson's reagent followed by reaction with DAST, into the difluorobenzochromenes (1c) (Bunelle, W. H. et al., J. Org. Chem. (1990), 55, pp. 768-770).

Alternatively, the lactones (1a) can, in accordance with Scheme V (Ringom, R. and Bennecke, T., Acta. Chem. Scand. (1999), 53, pp. 41-47), be reacted with LiAlH₄ in THF and subsequently reacted with DAST to give the fluorobenzochromenes (Id).

The above-mentioned alternative synthesis in which the cross-coupling is carried out in a first step with the correspondingly protected phenols and carboxylic acid esters is shown in Scheme IIIa on p. 16 using the example of a Negishi reaction.

-   -   in which     -   PG is a protecting group,     -   X is halogen, preferably Br,     -   X¹ and X², independently of one another, are halogen,     -   X¹ is preferably Cl, Br or I, particularly preferably Br or I,         very particularly preferably Br,     -   R″ is alkyl, preferably methyl, and     -   R and R′ are each, independently of one another, as defined         above for Scheme I.

After removal of the protecting group, the lactones can be obtained, for example, by simple heating in an inert solvent or by treatment with an acid or base.

Compounds of the formula I in which

-   -   are R¹, R²,         in which the         rings may also be heterocyclic rings,

can be obtained in accordance with Schemes VI to XX.

4-Bromo-3-fluoro-1-iodobenzene and 4-bromo-2-fluorophenol are likewise suitable as synthetic building blocks for a multiplicity of derivatives which can be converted into the corresponding target compounds analogously to the reaction sequences shown in Schemes I-V.

Cyclohexyl derivatives are obtained, for example, in accordance with Scheme X. Metallation of 4-bromo-3-fluoro-1-iodobenzene using n-butyllithium and addition onto cyclohexanones gives phenylcyclohexanols, from which 4-bromo-2-fluoro-1-cyclohexylbenzene derivatives are obtained after elimination of water and hydrogenation.

Aryl derivatives are obtained, for example, in accordance with Scheme XI. Direct Suzuki coupling of 4-bromo-3-fluoro-1-iodobenzene with the corresponding boronic acids enables the preparation of 1-aryl-4-bromo-2-fluoro derivatives.

Sonogashira coupling of 4-bromo-3-fluoro-1-iodobenzene with phenylacetylenes gives, as shown in Scheme XII, 4-bromo-2-fluorotolans. These can, as shown in Scheme XIII, either be hydrogenated to give ethylene-bridged compounds or converted into diketones by the method of V. O. Rogatchov, V. D. Filimonov, M. S. Yusubov, Synthesis (2001), 7, 1001-1003, from which tetrafluoroethylene-bridged compounds are obtained by reaction with sulfur tetrafluoride.

From 4-bromo-2-fluorophenol, hydroxyl compounds and triflates can be obtained as synthetic building blocks in accordance with Scheme XIV.

4-Bromo-2-fluorophenol is protected here using a suitable protecting group “PG” (for example benzyl); corresponding reaction in accordance with Schemes I to V and subsequent removal of the protecting group (for example by hydrogenation for benzyl as PG) enables the preparation of phenols and from these triflates (trifluoromethanesulfonates, TfO-).

-   -   in which, as in Schemes XV to XX,     -   G is Y—O or O—Y, and     -   Y is as defined above under the formula I.

The phenols obtained in this way can be converted into esters and ethers in accordance with Scheme XV.

-   -   in which R, as in Schemes XVI to XX, is as defined for R¹ under         the formula I.

CF₂O-bridged compounds are obtained in accordance with WO 02/48 073 and WO 01/64 667, as shown in Scheme XVI.

Suzuki coupling of the triflates obtained in accordance with Scheme XIV with etheneboronic acids enables the preparation of stilbenes (Scheme XVII).

Difluorostilbenes are accessible analogously by Stille reaction as described by L. Lu, D. J. Burton, Tetrahedron Lett. 1997, 38, 7673-7676, (Scheme XVIII).

Carbonylation of triflates by the method of S. Cacchi, P. G. Ciattini, E. Morera, G. Ortar, Tetrahedron Lett. (1986), 27, 3931-3934 gives carboxylic acid esters (Scheme XIX). After saponification to the corresponding carboxylic acids, reaction thereof with-phenols enables the preparation of, for example, phenyl esters.

The carboxylic acid esters obtained in accordance with Scheme XIX can be converted into difluorobenzyl ethers in accordance with WO 02/480 73 and WO 01/64 667, as shown in Scheme XX.

Examples of structures of preferred compounds of the formula I, in which R and R¹ have the respective meaning given for R¹ and R² respectively under the formula I, are given on the following pages.

The liquid-crystal media according to the invention comprise one or more compounds of the formula I.

In a preferred embodiment, the liquid-crystal media in accordance with the present invention comprise

-   -   a) one or more dielectrically negative compound(s) of the         formula I     -   in which     -   Y is —CO—, —CS—, —CH₂—, —CF₂— or —CHF—, preferably —CF₂—,     -   L¹ and L² are each, independently of one another, H, F, Cl or         —CN, preferably H or F, preferably at least one of L¹ and L² is         F, particularly preferably L¹ and L² are both F,         are each, independently of one another, and, if present more         than once, also independently of one another,     -   (a) a trans-1,4-cyclohexylene radical, in which, in addition,         one or two non-adjacent CH₂ groups may be replaced by —O— and/or         —S—,     -   (b) a 1,4-cyclohexenylene radical,     -   (c) a 1,4-phenylene radical, in which, in addition, one or two         non-adjacent CH groups may be replaced by N, or     -   (d) a radical selected from the group consisting of         1,4-bicyclo[2.2.2]octylene, 1,3-bicyclo[1.1.1]pentylene,         spiro[3.3]heptane-2,4-diyl, piperidine-1,4-diyl,         naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl and         1,2,3,4-tetrahydronaphthalene-2,6-diyl, preferably     -   R¹ and R² are each, independently of one another, H, halogen,         —CN, —SCN, —SF₅, —CF₃, —CHF₂, —CH₂F, —OCF₃, —OCHF₂, or an alkyl         group having from 1 to 15 carbon atoms which is monosubstituted         by CN or CF₃ or at least monosubstituted by halogen and in         which, in addition, one or more CH₂ groups may each,         independently of one another, be replaced by —O—, —S—, —CH═CH—,         —CF═CF—, —CF=CH—, —CH═CF—,         —CO—, —CO—O—, —O—CO— or —O—CO—O— in such a way that neither O         nor S atoms are linked directly to one another,     -   preferably one of     -   R¹ and R² is alkyl or alkoxy having from 1 to 12 carbon atoms,         alkoxyalkyl, alkenyl or alkenyloxy having from 2 to 12 carbon         atoms and the other, independently of the first, is likewise         alkyl or alkoxy having from 1 to 12 carbon atoms, alkoxyalkyl,         alkenyl or alkenyloxy having from 2 to 12 carbon atoms or         alternatively F, Cl, Br, —CN, —SCN, —SF₅, —CF₃, —CHF₂, —CH₂F,         —OCF₃ or —OCHF₂,     -   Z¹ and Z² are each, independently of one another, —CH₂—CH₂—,         —CF₂—CF₂—, —CF₂—CH₂—, —CH₂—CF₂—, —CH═CH—, —CF═CF—, —CF=CH—,         —CH═CF—, —C≡C—, —COO—, —OCO—, —CH₂O—, —OCH₂—, —CF₂O—, —OCF₂—, or         a combination of two of these groups, where no two O atoms are         bonded to one another,     -   preferably —(CH₂)₄—, —CH₂—CH₂—, —CF₂—CF₂—, —CH═CH—, —CF═CF—,         —C≡C—, —CH₂O—, —CF₂O— or a single bond,     -   particularly preferably —CH₂O—, —CH₂—CH₂—, —CF₂—CF₂—, —CF═CF—,         —CF₂O— or a single bond, and     -   n and m are each 0, 1 or 2, where     -   n+m is 0, 1, 2 or 3, preferably 0, 1 or 2, particularly         preferably 0 or 1,     -   b) one or more dielectrically negative compound(s) of the         formula II     -   in which     -   R²¹ and R²² are each, independently of one another, as defined         above for R¹ under the formula I,     -   Z²¹ and Z²² are each, independently of one another, as defined         above for Z¹ under the formula I,     -   at least one of the rings present         preferably         and         is         and the others are each, independently of one another,         preferably         particularly preferably         if present, is         very particularly preferably one of         and, if present,         preferably     -   L²¹ and L²¹ are both C—F or one of the two is N and the other is         C—F, preferably both are C—F, and     -   I is 0, 1 or 2, preferably 0 or 1;         and optionally     -   c) one or more dielectrically neutral compound(s) of the formula         III     -   in which     -   R³¹ and R³² are each, independently of one another, as defined         above for R¹ under the formula I, and     -   Z³¹, Z³² and Z³³ are each, independently of one another,         —CH₂CH₂—, —CH═CH—, —COO— or a single bond,         are each, independently of one another,     -   o and p, independently of one another, are 0 or 1, but         preferably     -   R³¹ and R³² are each, independently of one another, alkyl or         alkoxy having 1-5 carbon atoms or alkenyl having 2-5 carbon         atoms,         are each, independently of one another,         and very particularly preferably at least two of these rings are         where very particularly preferably two adjacent rings,         preferably         are linked directly.

The liquid-crystal media preferably comprise one or more compounds of the formula I which do not contain a biphenyl unit.

The liquid-crystal media particularly preferably comprise one or more compounds of the formula I in which two adjacent rings, preferably

are linked directly.

In a preferred embodiment, which may be identical with the embodiments just described, the liquid-crystal media comprise one or more compounds selected from the group consisting of the compounds of the formula I-3.

The liquid-crystal medium preferably comprises one or more compounds selected from the group consisting of the compounds of the formulae II-1 to II-3

in which

R²¹, R²², Z¹², Z²²,

and and I are each as defined above under the formula II. R²¹ is preferably alkyl, preferably having 1-5 carbon atoms, R is preferably alkyl or alkoxy, preferably each having from 1 to 5 carbon atoms, and Z²² and Z²¹, if present, are preferably a single bond.

The liquid-crystal medium particularly preferably comprises one or more compounds selected from the group consisting of the compounds of the formulae III-1 to III-3:

-   -   in which R³¹, R³², R³¹, Z³²         and are each as     -   defined above under the formula III.

The liquid-crystal medium especially preferably comprises one or more compounds selected from the group consisting of the compounds of the formulae III-1a to III-1d, III-1e, III-2a to III-2g, III-3a to III-3d and III-4a:

in which n and m are each, independently of one another, from 1 to 5, and o and p are each, independently both thereof and of one another, from 0 to 3,

in which R³¹ and R³³ are each as defined above under the formula III, preferably as defined above under the formula III-1, and the phenyl rings, in particular in the compounds III-2g and III-3c, may optionally be fluorinated, but not in such a way that the compounds are identical with those of the formula II and its sub-formulae. R³¹ is preferably n-alkyl having from 1 to 5 carbon atoms, particularly preferably having from 1 to 3 carbon atoms, and R³² is preferably n-alkyl or n-alkoxy having from 1 to 5 carbon atoms or alkenyl having from 2 to 6 carbon atoms. Of these, especial preference is given to compounds of the formulae III-1a to III-1d.

Preferred fluorinated compounds of the formulae III-2g and III-3c are the compounds of the formulae III-2g′ and III-3c′

in which R and R are each as defined above under the formula III, preferably as defined above under the formula III-2g or III-3c.

In the present application, unless expressly stated otherwise, the term compounds is taken to mean both one compound and a plurality of compounds.

The liquid-crystal med.ia according to the invention preferably have nematic phases of in each case from at least −20° C. to 80° C., preferably from −30° C. to 85° C. and very particularly preferably from −40° C. to 100° C. The term “have a nematic phase” here is taken to mean firstly that no smectic phase and no crystallisation are observed at low temperatures at the corresponding temperature and secondly also that no clearing occurs on heating from the nematic phase. The investigation at low temperatures is carried out in a flow viscometer at the corresponding temperature and checked by storage in test cells having.a layer thickness corresponding to the electro-optical application for at least 100 hours. The storage stability (t_(store) (T)) at the corresponding temperature (T) is quoted as the time up to which all three test cells show no change. At high temperatures, the clearing point is measured in capillaries by conventional methods.

Furthermore, the liquid-crystal media according to the invention are characterised by low optical anisotropy values.

The term “alkyl” preferably covers straight-chain and branched alkyl groups having from 1 to 7 carbon atoms, in particular the straight-chain groups methyl, ethyl, propyl, butyl, pentyl, hexyl and heptyl. Groups having from 2 to 5 carbon atoms are generally preferred.

The term “alkenyl” preferably covers straight-chain and branched alkenyl groups having from 2 to 7 carbon atoms, in particular the straight-chain groups. Particularly preferred alkenyl groups are C₂- to C₇-1 E-alkenyl, C₄- to C₇-3E-alkenyl, C₅- to C₇-4-alkenyl, C₆- to C₇-5-alkenyl and C₇-6-alkenyl, in particular C₂- to C₇-1E-alkenyl, C₄- to C₇-3E-alkenyl and C₅- to C₇-4-alkenyl. Examples of further preferred alkenyl groups are vinyl, 1E-propenyl, 1E-butenyl, 1E-pentenyl, 1E-hexenyl, 1E-heptenyl, 3-butenyl, 3E-pentenyl, 3E-hexenyl, 3E-heptenyl, 4-pentenyl, 4Z-hexenyl, 4E-hexenyl, 4Z-heptenyl, 5-hexenyl, 6-heptenyl and the like. Groups having up to 5 carbon atoms are generally preferred.

The term “fluoroalkyl” preferably covers straight-chain groups having a terminal fluorine, i.e. fluoromethyl, 2-fluoroethyl, 3-fluoropropyl, 4-fluoro-butyl, 5-fluoropentyl, 6-fluorohexyl and 7-fluoroheptyl. However, other positions of the fluorine are not excluded.

The term “oxaalkyl” or “alkoxyalkyl” preferably covers straight-chain radicals of the formula C_(n)H_(2n+1)—O—(CH₂)_(m), in which n and m are each, independently of one another, from 1 to 6. n is preferably 1 and m is preferably from 1. to 6.

Compounds containing a vinyl end group and compounds containing a methyl end group have low rotational viscosity.

In the present application, the term dielectrically positive compounds means compounds having a Δε of >1.5, dielectrically neutral compounds means those in which −1.5≦Δε≦1.5, and dielectrically negative compounds means those having a Δε of <−1.5. The dielectric anisotropy of the compounds is determined here by dissolving 10% of the compounds in a liquid-crystalline host and determining the capacitance of this mixture at 1 kHz in at least one test cell with a layer thickness of about 20 μm having a homeotropic surface alignment and at least one test cell with a layer thickness of about 20 μm having a homogeneous surface alignment. The measurement -voltage is typically from 0.5 V to 1.0 V, but is always less than the capacitive threshold of the respective liquid-crystal mixture.

The host mixture used for determining the applicationally relevant physical parameters is ZLI-4792 from Merck KGaA, Germany. As an exception, the determination of the dielectric anisotropy of dielectrically negative compounds is carried out using ZLI-2857, likewise from Merck KGaA, Germany. The values for the respective compound to be investigated are obtained from the change in the properties, for example the dielectric constants, of the host mixture after addition of the compound to be investigated and extrapolation to 100% of the compound employed.

The concentration employed for the compound to be investigated is 10%. If the solubility of the compound to be investigated is inadequate for this purpose, the concentration employed is, by way of exception, halved, i.e. reduced to 5%, 2.5%, etc., until the concentration is below the solubility limit.

The term threshold voltage usually relates to the optical threshold for 10% relative contrast (V₁₀). In relation to the liquid-crystal mixtures of negative .dielectric anisotropy, however, the term threshold voltage is used in the present application for the capacitive threshold voltage (V₀), also known as the Freedericksz threshold, unless explicitly stated otherwise.

All concentrations in this application, unless explicitly stated otherwise, are given in per cent by weight and relate to the corresponding mixture as a whole. All physical properties are and have been determined in accordance with “Merck Liquid Crystals, Physical Properties of Liquid Crystals”, status November 1997, Merck KGaA, Germany, and apply to a temperature of 20° C., unless explicitly stated otherwise. An is determined at 589 nm and Δε at 1 kHz.

In the case of the liquid-crystal media of negative dielectric anisotropy, the threshold voltage was determined as the capacitive threshold V₀ in cells with a liquid-crystal layer aligned homeotropically by means of lecithin.

The liquid-crystal media according to the invention may, if necessary, also comprise further additives and optionally also chiral dopants in the conventional amounts. The amount of these additives employed is in total from 0% to 10%, based on the amount of the mixture as a whole, preferably from 0.1% to 6%. The concentrations of the individual compounds employed are in each case preferably from 0.1 to 3%. The concentration of these and similar additives is not taken into account when indicating the concentrations and the concentration ranges of the liquid-crystal compounds in the liquid-crystal media.

The compositions consist of a plurality of compounds, preferably from 3 to 30, particularly preferably from 6 to 20 and very particularly preferably from 10 to 16 compounds, which are mixed in a conventional manner. In general, the desired amount of the components used in lesser amount is dissolved in the components making up the principal constituent, advantageously at elevated temperature. If the selected temperature is above the clearing point of the principal constituent, the completion of the dissolution process is particularly easy to observe. However, it is also possible to prepare the liquid-crystal mixtures in other conventional ways, for example using premixes or from a so-called “multibottle” system.

By means of suitable additives, the liquid-crystal phases according to the invention can be modified in such a way that they can be employed in any type of display and in particular of ECB display and IPS display that has been disclosed hitherto.

The examples below serve to illustrate the invention without representing a restriction. In the examples, the melting point T(C,N), the transition from the smectic (S) phase to the nematic (N) phase T(S,N) and the clearing point T(N,I) of a liquid-crystal substance are indicated in degrees Celsius. The various smectic phases are characterised by corresponding suffixes.

The percentages above and below are, unless explicitly stated otherwise, percent by weight, and the physical properties are the values at 20° C., unless explicitly stated otherwise.

All the temperature values indicated in this application are ° C. and all temperature differences are correspondingly differential degrees, unless explicitly stated otherwise.

In the synthesis examples and schemes, the abbreviations have the following meanings:

-   BuLi n-butyllithium, -   DAST diethylaminosulfur trifluoride, -   DCC dicyclohexylcarbodiimide, -   DMAP dimethylaminopyridine, -   DMF N,N-dimethylformamide, -   dppf 1,1′-bis(diphenylphosphino)ferrocene, -   dppp 1,3-bis(diphenylphosphino)propane, -   LDA lithium diisopropylamide, -   MBT MBT ether, methyl tert-butyl ether and -   THF tetrahydrofuran.

In the present application and in the examples below, the structures of the liquid-crystal compounds are indicated by means of acronyms, the transformation into chemical formulae taking place in accordance with Tables A and B below. All radicals C_(n)H_(2n+1) and C_(m)H_(2m+1) are straight-chain alkyl radicals having n and m carbon atoms respectively. The coding in Table B is self-evident. In Table A, only the acronym for the parent structure is indicated. In individual cases, the acronym for the parent structure is followed, separated by a hyphen, by a code for the substituents R¹, R², L¹, L² and L³: Code for R¹, R², L¹, L², L³ R¹ R² L¹ L² L³ nm C_(n)H_(2n+1) C_(m)H_(2m+1) H H H nOm C_(n)H_(2n+1) OC_(m)H_(2m+1) H H H nO.m OC_(n)H_(2n+1) C_(m)H_(2m+1) H H H nmFF C_(n)H_(2n+1) C_(m)H_(2m+1) F H F nOmFF C_(n)H_(2n+1) OC_(m)H_(2m+1) F H F nO.mFF OC_(n)H_(2n+1) C_(m)H_(2m+1) F H F nO.OmFF OC_(n)H_(2n+1) OC_(m)H_(2m+1) F H F n C_(n)H_(2n+1) CN H H H nN.F C_(n)H_(2n+1) CN F H H nN.F.F C_(n)H_(2n+1) CN F F H nF C_(n)H_(2n+1) F H H H nF.F C_(n)H_(2n+1) F F H H nF.F.F C_(n)H_(2n+1) F F F H nCl C_(n)H_(2n+1) Cl H H H nCl.F C_(n)H_(2n+1) Cl F H H nCl.F.F C_(n)H_(2n+1) Cl F F H nmF C_(n)H_(2n+1) C_(m)H_(2m+1) F H H nCF₃ C_(n)H_(2n+1) CF₃ H H H nOCF₃ C_(n)H_(2n+1) OCF₃ H H H nOCF₃.F C_(n)H_(2n+1) OCF₃ F H H nOCF₃.F.F C_(n)H_(2n+1) OCF₃ F F H nOCF₂ C_(n)H_(2n+1) OCHF₂ H H H nOCF₂.F.F C_(n)H_(2n+1) OCHF₂ F F H nS C_(n)H_(2n+1) NCS H H H rVsN C_(r)H_(2r+1)—CH═CH—C_(s)H_(2s)— CN H H H nEsN C_(r)H_(2r+1)—O—C_(s)H_(2s)— CN H H H nAm C_(n)H_(2n+1) COOC_(m)H_(2m+1) H H H nF.Cl C_(n)H_(2n+1) F Cl H H

TABLE A

TABLE B

EXAMPLES

The following examples are intended to explain the invention without limiting it. Above and below, percentages are per cent by weight. All temperatures are indicated in degrees Celsius. An denotes the optical anisotropy (589 nm, 20° C.), Δε the dielectric anisotropy (1 kHz, 20° C.), H.R. the voltage holding ratio (at 100° C., after 5 minutes in the oven, 1 V). V₁₀, V₅₀ and V₉₀ (the threshold voltage, mid-grey voltage and saturation voltage respectively) and V₀ (the capacitive threshold voltage) were each determined at 20° C.

Substance Examples Example 1 (4,7-Difluoro-8-methyl-3-pentyl-6H-benzo[c]chromen-6-one) 1.1 Preparation of 4-bromo-2-fluoro-1-pentylbenzene

190 g (0.600 mol) of 4-bromo-2-fluoro-1-iodobenzene and 65.3 ml of 1-pentyne were dissolved in a mixture of 900 ml of THF and 1.2 l of triethylamine and cooled to 10° C., and 1.14 g (6 mmol) of copper(I) iodide and 8.42 g (12 mmol) of bis(triphenylphosphine)palladium(II) chloride were added. The batch was stirred overnight at room temperature, water and MTB ether were subsequently added, and the mixture was stirred for a further 5 minutes. The reaction mixture was filtered through Celite® with suction, and the phases were separated. The aqueous phase was extracted twice with MTB ether, and the combined organic phases were washed three times with water, dried over sodium sulfate and evaporated under reduced pressure. The crude product was filtered through silica gel with n-heptane, giving 129 g of 4-bromo-2-fluoro-1-pent-1-ynylbenzene as a yellow liquid. Hydrogenation on palladium/activated carbon (10%) in THF gave 131 g (100%) of 4-bromo-2-fluoro-1-pentylbenzene as a yellow liquid.

1.2 Preparation of 6-bromo-2-fluoro-3-pentylphenol

132 g (0.583 mol) of 4-bromo-2-fluoro-1-pentylbenzene were dissolved in 900 ml of THF, and 295 ml of a 2 molar solution of LDA in THF were added dropwise at −70° C. After 1 hour, 65.9 ml (0.590 mol) of trimethyl borate were added, and the mixture was stirred for a further 1 hour and then acidified at −15° C. using 150 ml of 50 per cent acetic acid. The batch was subsequently warmed to 30° C., and 139 ml (1.61 mol) of 35 per cent hydrogen peroxide solution were added dropwise. After 1 hour, the mixture was diluted with water, and the organic phase was separated off. The combined organic phases were washed twice with ammonium iron(II) sulfate solution and once with water, dried over sodium sulfate and evaporated under reduced pressure.

Filtration of the crude product through silica gel with n-heptane/1-chlorobutane (3:1) gave 86.0 g (61% of theory) of 6-bromo-2-fluoro-3-pentylphenol as colourless crystals.

1.3 Preparation of 6-bromo-2-fluoro-3-methylbenzoic acid

50 ml (0.385 mol) of 4-bromo-2-fluorotoluene were dissolved in 750 ml of THF, and 231 ml (0.462 mol) of a 2 M solution of LDA in THF were added dropwise at −70° C. After 70 minutes, 37.2 g (0.846 mol) of carbon dioxide were passed in, and the batch was allowed to thaw. After acidification using conc. hydrochloric acid, the solution was extracted with MTB ether, and the combined organic phases were washed with water, dried over sodium sulfate and evaporated under reduced pressure. Crystallisation of the crude product from 1-chlorobutane gave 44.1 g (49%) of 6-bromo-2-fluoro-3-methylbenzoic acid as white crystals.

1.4 Preparation of 6-bromo-2-fluoro-3-pentylphenyl 6-bromo-2-fluoro-3-methylbenzoate

43.2 g (0.165 mol) of 6-bromo-2-fluoro-3-pentylphenol, 40.5 g (0.173 mol) of 6-bromo-2-fluoro-3-methylbenzoic acid and 3.52 g (29 mmol) of 4-(dimethylamino)pyridine were initially introduced in 300 ml of dichloro-methane, and a solution of 35.7 g (0.172 mol) of N,N-dicyclohexyl-carbodiimide in 80 ml of dichloromethane was added. The batch was stirred overnight at room temperature, and 4.16 g (33 mmol) of oxalic acid were subsequently added. After 1 hour, the precipitated solid was filtered off, and the filtrate was evaporated under reduced pressure. The crude product was filtered through silica gel with n-heptane/1-chlorobutane (1:1), giving 72.7 g (91% of theory) of 6-bromo-2-fluoro-3-pentylphenyl 6-bromo-2-fluoro-3-methylbenzoate as a colourless oil.

1.5 Preparation of 4,7-difluoro-8-methyl-3-pentyl-6H-benzo[c]chromen-6-one

56.2 g (118 mmol) of 6-bromo-2-fluoro-3-pentylphenyl 6-bromo-2-fluoro-3-methylbenzoate were dissolved in 650 ml of DMF, and the mixture was refluxed for 48 hours in the presence of 75.1 g (1.18 mmol) of copper powder. The mixture was subsequently diluted with water and extracted with ethyl acetate. The extracts were combined, dried over Na₂SO₄ and evaporated. The crude product was recrystallised from 1-chlorobutane, giving 9.60 g of the lactone as a colourless solid. This corresponds to a yield of 26%.

The physical properties of the compound are shown in the following table.

Examples 2 to 120

The following are prepared analogously to Example 1:

Phase sequence T*(N,I)/ No. R¹ R² T/° C. Δε* ° C. 2 CH₃ CH₃ C 237 I  3 CH₃ C₂H₅  4 CH₃ n-C₃H₇  5 CH₃ n-C₄H₉  1 CH₃ n-C₅H₁₁ C 104 I −17.8 22  6 CH₃ n-C₆H₁₃  7 CH₃ n-C₇H₁₅  8 CH₃ CH₃O  9 CH₃ C₂H₅O  10 CH₃ n-C₃H₇O  11 CH₃ n-C₄H₉O  12 CH₃ CH₂═CH  13 CH₃ E-CH₃—CH═CH  14 CH₃ CH₂═CH—O  15 CH₃ CH₂═CH—CH₂O  16 C₂H₅ CH₃  17 C₂H₅ C₂H₅  18 C₂H₅ n-C₃H₇  19 C₂H₅ n-C₄H₉  20 C₂H₅ n-C₅H₁₁  21 C₂H₅ n-C₆H₁₃  22 C₂H₅ n-C₇H₁₇  23 C₂H₅ CH₃O  24 C₂H₅ C₂H₅O  25 C₂H₅ n-C₃H₇O  26 C₂H₅ n-C₄H₉O  27 C₂H₅ CH₂═CH  28 C₂H₅ E-CH₃—CH═CH  29 C₂H₅ CH₂═CH—O  30 C₂H₅ CH₂═CH—CH₂O  31 n-C₃H₇ CH₃  32 n-C₃H₇ C₂H₅  33 n-C₃H₇ n-C₃H₇  34 n-C₃H₇ n-C₄H₉  35 n-C₃H₇ n-C₅H₁₁ C 103 I −19.0 7  36 n-C₃H₇ n-C₆H₁₃  37 n-C₃H₇ n-C₇H₁₅  38 n-C₃H₇ CH₃O  39 n-C₃H₇ C₂H₅O  40 n-C₃H₇ n-C₃H₇O  41 n-C₃H₇ n-C₄H₉O  42 n-C₃H₇ CH₂═CH  43 n-C₃H₇ E-CH₃—CH═CH  44 n-C₃H₇ CH₂═CH—O  45 n-C₃H₇ CH₂═CH—CH₂O  46 n-C₄H₉ CH₃  47 n-C₄H₉ C₂H₅  48 n-C₄H₉ n-C₃H₇  49 n-C₄H₉ n-C₄H₉  50 n-C₄H₉ n-C₅H₁₁  51 n-C₄H₉ n-C₆H₁₃  52 n-C₄H₉ n-C₇H₁₅  53 n-C₄H₉ CH₃O  54 n-C₄H₉ C₂H₅O  55 n-C₄H₉ n-C₃H₇O  56 n-C₄H₉ n-C₄H₉O  57 n-C₄H₉ CH₂═CH  58 n-C₄H₉ E-CH₃—CH═CH  59 n-C₄H₉ CH₂═CH—O  60a n-C₄H₉ CH₂═CH—CH₂O  60b n-C₅H₁₁ n-C₄H₉O C 130 I −23.5 57  61 CH₃O CH₃  62 CH₃O C₂H₅  63 CH₃O n-C₃H₇  64 CH₃O n-C₄H₉  65 CH₃O n-C₅H₁₁  66 CH₃O n-C₆H₁₃  67 CH₃O n-C₇H₁₅  68 CH₃O CH₃O  69 CH₃O C₂H₅O  70 CH₃O n-C₃H₇O  71 CH₃O n-C₄H₉O  72 CH₃O CH₂═CH  73 CH₃O E-CH₃—CH═CH  74 CH₃O CH₂═CH—O  75 CH₃O CH₂═CH—CH₂O  76 C₂H₅O CH₃  77 C₂H₅O C₂H₅  78 C₂H₅O n-C₃H₇  79 C₂H₅O n-C₄H₉  80 C₂H₅O n-C₅H₁₁ C 137 I  81 C₂H₅O n-C₆H₁₃  82 C₂H₅O n-C₇H₁₅  83 C₂H₅O CH₃O  84 C₂H₅O C₂H₅O  85 C₂H₅O n-C₃H₇O  86 C₂H₅O n-C₄H₉O  87 C₂H₅O CH₂═CH  88 C₂H₅O E-CH₃—CH═CH  89 C₂H₅O CH₂═CH—O  90 C₂H₅O CH₂═CH—CH₂O  91 CH₂═CH CH₃  92 CH₂═CH C₂H₅  93 CH₂═CH n-C₃H₇  94 CH₂═CH n-C₄H₉  95 CH₂═CH n-C₅H₁₁  96 CH₂═CH n-C₆H₁₃  97 CH₂═CH n-C₇H₁₅  98 CH₂═CH CH₃O  99 CH₂═CH C₂H₅O 100 CH₂═CH n-C₃H₇O 101 CH₂═CH n-C₄H₉O 102 CH₂═CH CH₂═CH 103 CH₂═CH E-CH₃—CH═CH 104 CH₂═CH CH₂═CH—O 105 CH₂═CH CH₂═CH—CH₂O 106 CH₂═CH—O CH₃ 107 CH₂═CH—O C₂H₅ 108 CH₂═CH—O n-C₃H₇ 109 CH₂═CH—O n-C₄H₉ 110 CH₂═CH—O n-C₅H₁₁ 111 CH₂═CH—O n-C₆H₁₃ 112 CH₂═CH—O n-C₇H₁₅ 113 CH₂═CH—O CH₃O 114 CH₂═CH—O C₂H₅O 115 CH₂═CH—O n-C₃H₇O 116 CH₂═CH—O n-C₄H₉O 117 CH₂═CH—O CH₂═CH 118 CH₂═CH—O E-CH₃—CH═CH 119 CH₂═CH—O CH₂═CH—O 120 CH₂═CH—O CH₂═CH—CH₂O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Example 121 (4,7-Difluoro-8-methyl-3-pentyl-6H-benzo[c]chromene) Preparation of 4,7-difluoro-8-methyl-3-pentyl-6H-benzo[c]chromene

2.00 g (6.33 mmol) of the compound from Example 1 were dissolved in 12 ml of THF. 2.56 ml (23 mmol) of boron trifluoride/THF complex were added to this solution with ice-cooling. 12 ml of diethylene glycol dimethyl ether and, in portions, 0.58 g (15 mmol) of sodium borohydride were then added successively, and the mixture was stirred at room temperature (about 20° C.) for 16 hours. The reaction solution was hydrolysed using ice-water and extracted with MTB ether, and the extracts were combined and dried over Na₂SO₄ and evaporated. The crude product was recrystallised from n-heptane, giving 1.60 g of colourless crystals of the benzochromene. This corresponds to a yield of 83%.

Examples 122 to 240 The following are prepared analogously to Example 121:

Phase sequence T*(N,I)/ No. R¹ R² T/° C. Δε* ° C. 122 CH₃ CH₃ C 110 I −3.2 27 123 CH₃ C₂H₅ 124 CH₃ n-C₃H₇ 125 CH₃ n-C₄H₉ 121 CH₃ n-C₅H₁₁ Tg −60 C −3.1 6 42 I 126 CH₃ n-C₆H₁₃ 127 CH₃ n-C₇H₁₅ 128 CH₃ CH₃O 129 CH₃ C₂H₅O 130 CH₃ n-C₃H₇O 131 CH₃ n-C₄H₉O 132 CH₃ CH₂═CH 133 CH₃ E-CH₃—CH═CH 134 CH₃ CH₂═CH—O 135 CH₃ CH₂═CH—CH₂O 136 C₂H₅ CH₃ 137 C₂H₅ C₂H₅ 138 C₂H₅ n-C₃H₇ 139 C₂H₅ n-C₄H₉ 140 C₂H₅ n-C₅H₁₁ 141 C₂H₅ n-C₆H₁₃ 142 C₂H₅ n-C₇H₁₅ 143 C₂H₅ CH₃O 144 C₂H₅ C₂H₅O 145 C₂H₅ n-C₃H₇O 146 C₂H₅ n-C₄H₉O 147 C₂H₅ CH₂═CH 148 C₂H₅ E-CH₃—CH═CH 149 C₂H₅ CH₂═CH—O 150 C₂H₅ CH₂═CH—CH₂O 151 n-C₃H₇ CH₃ 152 n-C₃H₇ C₂H₅ 153 n-C₃H₇ n-C₃H₇ 154 n-C₃H₇ n-C₄H₉ 155 n-C₃H₇ n-C₅H₁₁ C 34 I −2.7 156 n-C₃H₇ n-C₆H₁₃ 157 n-C₃H₇ n-C₇H₁₅ 158 n-C₃H₇ CH₃O 159 n-C₃H₇ C₂H₅O 160 n-C₃H₇ n-C₃H₇O 161 n-C₃H₇ n-C₄H₉O 162 n-C₃H₇ CH₂═CH 163 n-C₃H₇ E-CH₃—CH═CH 164 n-C₃H₇ CH₂═CH—O 165 n-C₃H₇ CH₂═CH—CH₂O 166 n-C₄H₉ CH₃ 167 n-C₄H₉ C₂H₅ 168 n-C₄H₉ n-C₃H₇ 169 n-C₄H₉ n-C₄H₉ 170 n-C₄H₉ n-C₅H₁₁ 171 n-C₄H₉ n-C₆H₁₃ 172 n-C₄H₉ n-C₇H₁₅ 173 n-C₄H₉ CH₃O 174 n-C₄H₉ C₂H₅O 175 n-C₄H₉ n-C₃H₇O 176 n-C₄H₉ n-C₄H₉O 177 n-C₄H₉ CH₂═CH 178 n-C₄H₉ E-CH₃—CH═CH 179 n-C₄H₉ CH₂═CH—O 180a n-C₄H₉ CH₂═CH—CH₂O 180b n-C₅H₁₁ n-C₄H₉O 181 CH₃O CH₃ 182 CH₃O C₂H₅ 183 CH₃O n-C₃H₇ 184 CH₃O n-C₄H₉ 185 CH₃O n-C₅H₁₁ 186 CH₃O n-C₆H₁₃ 187 CH₃O n-C₇H₁₅ 188 CH₃O CH₃O 189 CH₃O C₂H₅O 190 CH₃O n-C₃H₇O 191 CH₃O n-C₄H₉O 192 CH₃O CH₂═CH 193 CH₃O E-CH₃—CH═CH 194 CH₃O CH₂═CH—O 195 CH₃O CH₂═CH—CH₂O 196 C₂H₅O CH₃ 197 C₂H₅O C₂H₅ 198 C₂H₅O n-C₃H₇ 199 C₂H₅O n-C₄H₉ 200 C₂H₅O n-C₅H₁₁ Tg −39 C −6.5 39 55 N (17.4) I 201 C₂H₅O n-C₆H₁₃ 202 C₂H₅O n-C₇H₁₅ 203 C₂H₅O CH₃O 204 C₂H₅O C₂H₅O 205 C₂H₅O n-C₃H₇O 206 C₂H₅O n-C₄H₉O 207 C₂H₅O CH₂═CH 208 C₂H₅O E-CH₃—CH═CH 209 C₂H₅O CH₂═CH—O 210a C₂H₅O CH₂═CH—CH₂O 210b n-C₄H₉O n-C₅H₁₁ 211 CH₂═CH CH₃ 212 CH₂═CH C₂H₅ 213 CH₂═CH n-C₃H₇ 214 CH₂═CH n-C₄H₉ 215 CH₂═CH n-C₅H₁₁ 216 CH₂═CH n-C₆H₁₃ 217 CH₂═CH n-C₇H₁₅ 218 CH₂═CH CH₃O 219 CH₂═CH C₂H₅O 220 CH₂═CH n-C₃H₇O 221 CH₂═CH n-C₄H₉O 222 CH₂═CH CH₂═CH 223 CH₂═CH E-CH₃—CH═CH 224 CH₂═CH CH₂═CH—O 225 CH₂═CH CH₂═CH—CH₂O 226 CH₂═CH—O CH₃ 227 CH₂═CH—O C₂H₅ 228 CH₂═CH—O n-C₃H₇ 229 CH₂═CH—O n-C₄H₉ 230 CH₂═CH—O n-C₅H₁₁ 231 CH₂═CH—O n-C₆H₁₃ 232 CH₂═CH—O n-C₇H₁₅ 233 CH₂═CH—O CH₃O 234 CH₂═CH—O C₂H₅O 235 CH₂═CH—O n-C₃H₇O 236 CH₂═CH—O n-C₄H₉O 237 CH₂═CH—O CH₂═CH 238 CH₂═CH—O E-CH₃—CH═CH 239 CH₂═CH—O CH₂═CH—O 240 CH₂═CH—O CH₂═CH—CH₂O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Example 241 (8-Ethoxy-4,6,6,7-tetrafluoro-3-pentyl-6H-benzo[c]-chromene) Preparation of 8-ethoxy-4,6,6,7-tetrafluoro-3-pentyl-6H-benzo[c]chromene

4.00 g (11.5 mmol) of the compound from Example 80 and 5.14 g (12.7 mmol) of Lawesson's reagent were dissolved in 60 ml of chlorobenzene, and the mixture was refluxed for 48 hours. The batch was subsequently evaporated and subjected to conventional purification, giving 2.90 g (8.00 mmol) of the corresponding thionolactone as an orange solid. This corresponds to a yield of 69%.

The thionolactone was dissolved in 40 ml of dichloromethane. 2.1 ml (16.1 mmol) of DAST were then added, and the mixture was stirred at about 20° C. for 16 hours and subjected to conventional purification. The crude product was purified via silica gel with a mixture of n-heptane/ethyl acetate (9:1) and recrystallised from ethanol, giving 0.46 9 of the difluorobenzochromene. This corresponds to a yield of 15%.

Examples 242 to 360

The following are prepared analogously to Example 241:

Phase sequence No. R¹ R² T/° C. Δε* 242 CH₃ CH₃ 243 CH₃ C₂H₅ 244 CH₃ n-C₃H₇ 245 CH₃ n-C₄H₉ 246 CH₃ n-C₅H₁₁ 247 CH₃ n-C₆H₁₃ 248 CH₃ n-C₇H₁₅ 249 CH₃ CH₃O 250 CH₃ C₂H₅O 251 CH₃ n-C₃H₇O 252 CH₃ n-C₄H₉O 253 CH₃ CH₂═CH 254 CH₃ E-CH₃—CH═CH 255 CH₃ CH₂═CH—O 256 CH₃ CH₂═CH—CH₂O 257 C₂H₅ CH₃ 258 C₂H₅ C₂H₅ 259 C₂H₅ n-C₃H₇ 260 C₂H₅ n-C₄H₉ 261 C₂H₅ n-C₅H₁₁ 262 C₂H₅ n-C₆H₁₃ 263 C₂H₅ n-C₇H₁₅ 264 C₂H₅ CH₃O 265 C₂H₅ C₂H₅O 266 C₂H₅ n-C₃H₇O 267 C₂H₅ n-C₄H₉O 268 C₂H₅ CH₂═CH 269 C₂H₅ E-CH₃—CH═CH 270 C₂H₅ CH₂═CH—O 271 C₂H₅ CH₂═CH—CH₂O 272 n-C₃H₇ CH₃ 273 n-C₃H₇ C₂H₅ 274 n-C₃H₇ n-C₃H₇ 275 n-C₃H₇ n-C₄H₉ 276 n-C₃H₇ n-C₅H₁₁ C 53 I −10.4 277 n-C₃H₇ n-C₆H₁₃ 278 n-C₃H₇ n-C₇H₁₅ 279 n-C₃H₇ CH₃O 280 n-C₃H₇ C₂H₅O 281 n-C₃H₇ n-C₃H₇O 282 n-C₃H₇ n-C₄H₉O 283 n-C₃H₇ CH₂═CH 284 n-C₃H₇ E-CH₃—CH═CH 285 n-C₃H₇ CH₂═CH—O 286 n-C₃H₇ CH₂═CH—CH₂O 287 n-C₄H₉ CH₃ 288 n-C₄H₉ C₂H₅ 289 n-C₄H₉ n-C₃H₇ 290 n-C₄H₉ n-C₄H₉ 291 n-C₄H₉ n-C₅H₁₁ 292 n-C₄H₉ n-C₆H₁₃ 293 n-C₄H₉ n-C₇H₁₅ 294 n-C₄H₉ CH₃O 295 n-C₄H₉ C₂H₅O 296 n-C₄H₉ n-C₃H₇O 297 n-C₄H₉ n-C₄H₉O 298 n-C₄H₉ CH₂═CH 299 n-C₄H₉ E-CH₃—CH═CH 300 n-C₄H₉ CH₂═CH—O 301a n-C₄H₉ CH₂═CH—CH₂O 301b n-C₅H₁₁ n-C₄H₉O 302 CH₃O CH₃ 303 CH₃O C₂H₅ 304 CH₃O n-C₃H₇ 305 CH₃O n-C₄H₉ 306 CH₃O n-C₅H₁₁ 307 CH₃O n-C₆H₁₃ 308 CH₃O n-C₇H₁₅ 309 CH₃O CH₃O 310 CH₃O C₂H₅O 311 CH₃O n-C₃H₇O 312 CH₃O n-C₄H₉O 313 CH₃O CH₂═CH 314 CH₃O E-CH₃—CH═CH 315 CH₃O CH₂═CH—O 316 CH₃O CH₂═CH—CH₂O 317 C₂H₅O CH₃ 318 C₂H₅O C₂H₅ 319 C₂H₅O n-C₃H₇ 320 C₂H₅O n-C₄H₉ 241 C₂H₅O n-C₅H₁₁ C 85 I −15.4 321 C₂H₅O n-C₆H₁₃ 322 C₂H₅O n-C₇H₁₅ 323 C₂H₅O CH₃O 324 C₂H₅O C₂H₅O 325 C₂H₅O n-C₃H₇O 326 C₂H₅O n-C₄H₉O 327 C₂H₅O CH₂═CH 328 C₂H₅O E-CH₃—CH═CH 329 C₂H₅O CH₂═CH—O 330a C₂H₅O CH₂═CH—CH₂O 330b n-C₄H₉O n-C₅H₁₁ 331 CH₂═CH CH₃ 332 CH₂═CH C₂H₅ 333 CH₂═CH n-C₃H₇ 334 CH₂═CH n-C₄H₉ 335 CH₂═CH n-C₅H₁₁ 336 CH₂═CH n-C₆H₁₃ 337 CH₂═CH n-C₇H₁₅ 338 CH₂═CH CH₃O 339 CH₂═CH C₂H₅O 340 CH₂═CH n-C₃H₇O 341 CH₂═CH n-C₄H₉O 342 CH₂═CH CH₂═CH 343 CH₂═CH E-CH₃—CH═CH 344 CH₂═CH CH₂═CH—O 345 CH₂═CH CH₂═CH—CH₂O 346 CH₂═CH—O CH₃ 347 CH₂═CH—O C₂H₅ 348 CH₂═CH—O n-C₃H₇ 349 CH₂═CH—O n-C₄H₉ 350 CH₂═CH—O n-C₅H₁₁ 351 CH₂═CH—O n-C₆H₁₃ 352 CH₂═CH—O n-C₇H₁₅ 353 CH₂═CH—O CH₃O 354 CH₂═CH—O C₂H₅O 355 CH₂═CH—O n-C₃H₇O 356 CH₂═CH—O n-C₄H₉O 357 CH₂═CH—O CH₂═CH 358 CH₂═CH—O E-CH₃—CH═CH 359 CH₂═CH—O CH₂═CH—O 360 CH₂═CH—O CH₂═CH—CH₂O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Example 361a (3-Butoxy-4,6,6,7-tetrafluoro-8-(4-pentylcyclohexyl)-6H-benzo[c]chromene) 361.1 Preparation of 4-bromo-2-fluoro-1-(4-pentylcyclohex-1 -enyl)benzene

200 g (0.665 mol) of 1-bromo-3-fluoro-4-iodobenzene were dissolved in 800 ml of tetrahydrofuran, and 440 ml (0.698 mmol) of a 15 per cent solution of n-butyllithium in hexane were added dropwise at −70° C. After 30 minutes, a solution of 117 g (0.698 mol) of 4-pentylcyclohexanone in 200 ml of tetrahydrofuran was added, and the batch was left to stirr for 60 minutes, hydrolysed using water and acidified using conc. hydrochloric acid. The organic phase was separated off, washed with water and dried over sodium sulfate, and the solvent was removed under reduced pressure. The crude product was subsequently dissolved in 1.4 l of toluene and, after addition of 6 g of toluenesulfonic acid, heated on a water separator until water of reaction was no longer separated off. The solution was washed with water and evaporated, and the residue was filtered through silica gel with n-heptane, giving 124 g (58%) of 4-bromo-2-fluoro-1-(4-pentylcyclohex-1-enyl)benzene as a yellow oil.

361.2 Preparation of 4-bromo-2-fluoro-1-(4-pentylcyclohexyl)benzene

124 g (0.382 mol) of 4-bromo-2-fluoro-1-(4-pentylcyclohex-1-enyl)benzene were hydrogenated to completion at 5 bar and 50° C. in tetrahydrofuran on platinum/activated carbon catalyst. Filtration and removal of the solvent under reduced pressure gave 114 g (80%) of a mixture of cis- and trans-4-bromo-2-fluoro-1-(4-pentylcyclohexyl)benzene as a yellow oil. For isomerisation, this was dissolved in 200 ml of dichloromethane and added dropwise to a suspension of 12.5 g (95.7 mmol) of aluminium chloride in 220 ml of dichloromethane. After 30 minutes, 300 ml of water were added, and the organic phase was separated off, washed with water and dried over sodium sulfate. The solvent was removed under reduced pressure, and the residue was filtered through silica gel with n-pentane, giving 85.2 g of crude product having a content of trans-4-bromo-2-fluoro-1-(4-pentyl-cyclohexyl)benzene of 52.8% and a content of cis-4-bromo-2-fluoro-1-(4-pentylcyclohexyl)benzene of 9.7% as a yellow liquid, which was employed in the next step without further purification.

361.3 Preparation of trans-6-bromo-2-fluoro-3-(4-pentylcyclohexyl)benzoic acid

85.2 g (0.163 mol) of the crude product from the preceding step were initially introduced in 400 ml of tetrahydrofuran at −70° C., and a solution of lithium diisopropylamide, prepared from 213 ml of 15 per cent n-butyllithium in hexane and 46 ml (0.326 mmol) of diisopropylamine in 100 ml of tetrahydrofuran, was added dropwise. After 1 hour, 22.9 g (0.521 mol) of carbon dioxide were passed in. The batch was allowed to thaw, acidified using conc. hydrochloric acid and extracted twice with MTB ether. The combined organic phases were washed with water and dried over sodium sulfate, and the solvent was removed under reduced pressure. Crystallisation from n-heptane gave 17 g (28%) of trans-6-bromo-2-fluoro-3-(4-pentylcyclohexyl)benzoic acid as colourless crystals.

361.4 Preparation of methyl trans-6-bromo-2-fluoro-3-(4-pentylcyclohexyl)-benzoate

17.1 g (46.0 mmol) of trans-6-bromo-2-fluoro-3-(4-pentylcyclohexyl)-benzoic acid were dissolved in 70 ml of acetone, 7.66 g (55.4 mmol) of potassium carbonate and 3.14 ml (50.6 mmol) of methyl iodide were added, and the mixture was refluxed overnight. The batch was filtered, and the solvent was distilled off, giving 18 g (100%) of methyl 6-bromo-2-fluoro-3-(4-pentylcyclohexyl)benzoate as a colourless oil, which was reacted further without further purification.

361.5 Preparation of 1-bromo-4-butoxy-3-fluoro-2-(2-methoxyethoxy-methoxy)benzene

Analogously to Examples 841.1 and 841.4, 4-bromo-2-fluorophenol gave 6-bromo-3-butoxy-2-fluorophenol as a brown oil (80%, 2 steps).

60.4 ml (0.355 mol) of ethyldiisopropylamine were added with ice-cooling to 77.4 g (0.294 mol) of 6-bromo-3-butoxy-2-fluorophenol dissolved in 500 ml of dichloromethane, 40.3 ml (0.355 mol) of 2-methoxyethoxymethyl chloride were added dropwise, and the mixture was left to stirr overnight at room temperature. The batch was hydrolysed using water, extracted with dichloromethane and evaporated, and the crude product was filtered through silica gel with n-heptane/MTB ether (3:1), giving 103 g (99%) of 1-bromo-4-butoxy-3-fluoro-2-(2-methoxyethoxymethoxy)benzene as a yellow oil.

361.6 Preparation of 3-butoxy-4,7-difluoro-8-(4-pentylcyclohexyl)-benzo[c]chromen-6-one

16.4 g (0.046 mol) of 1-bromo-4-butoxy-3-fluoro-2-(2-methoxyethoxy-methoxy)benzene were dissolved in 20 ml of tetrahydrofuran, and 31.6 ml (0.052 mol) of a 15 per cent solution of n-butyllithium in hexane were added at −70° C. After addition of a solution of 5.94 g (0.027 mol) of zinc bromide in 30 ml of tetrahydrofuran, the batch was allowed to thaw, and the resultant solution was added at the boiling point to a mixture of 18 g (0.046 mol) of methyl 6-bromo-2-fluoro-3-(4-pentylcyclohexyl)benzoate and 730 mg (1.00 mmol) of Pd(dppf)₂Cl₂ in 60 ml of tetrahydrofuran. The batch was refluxed for 4 hours, stirred overnight at room temperature, acidified using dilute hydrochloric acid and extracted with MTB ether. The combined organic phases were washed with water, dried over sodium sulfate and evaporated. The crude product was chromatographed over silica gel with n-pentane/MTB ether (3:1), giving 14.6 g (55%) of methyl 4′-butoxy-3,3′-difluoro-2′-(2-methoxyethoxymethoxy)-4-(4-pentylcyclohexyl)-biphenyl-2-carboxylate as a yellow oil. This was dissolved in 56 ml of tetrahydrofuran, 11 ml of conc. hydrochloric acid were added, and the mixture was stirred overnight at room temperature. The precipitated product was filtered off with suction, washed with ethyl acetate and dried, giving 7.6 g (68%) of 3-butoxy-4,7-difluoro-8-(4-pentylcyclohexyl)-benzo[c]chromen-6-one as colourless crystals.

361.7 Preparation of 3-butoxy-4,7-difluoro-8-(4-pentylcyclohexyl)-benzo[c]chromene-6-thione

11.7 g (25.6 mmol) of 3-butoxy-4,7-difluoro-8-(4-pentylcyclohexyl)-benzo[c]chromen-6-one and 11.4 g (28.2 mmol) of Lawesson's reagent were refluxed for 16 hours in 130 ml of chlorobenzene. The solution was subsequently filtered through silica gel and evaporated, and the crude product was purified by crystallisation from MTB ether, giving 7.9 g (65%) of 3-butoxy-4,7-difluoro-8-(4-pentylcyclohexyl)benzo[c]chromene-6-thione as yellow crystals.

361.8 Preparation of 3-butoxy-4,6,6,7-tetrafluoro-8-(4-pentylcyclohexyl)-6H-benzo[c]chromene

2.00 g (4.18 mmol) of 3-butoxy-4,7-difluoro-8-(4-pentylcyclohexyl)benzo-[c]chromene-6-thione were dissolved in 20 ml of dichloromethane and cooled to −70° C., 0.55 ml (20 mmol) of a 65 percent solution of hydrogen fluoride in pyridine was added, and a suspension of 2.56 g (8.36 mmol) of 1,3-dibromo-5,5-dimethylhydantoin in 12 ml of dichloromethane was added in portions. After 2 hours, the batch was allowed to thaw, and was neutralised using sat. sodium hydrogencarbonate solution and extracted with dichloromethane. The organic phases were washed with water, dried over sodium sulfate and evaporated, and the crude product was chromatographed over silica gel with heptane/toluene (1:2). Crystallisation from n-heptane gave 1.0 g (52%) of 3-butoxy-4,6,6,7-tetrafluoro-8-(4-pentylcyclohexyl)-6H-benzo[c]chromene as colourless crystals of melting point 99° C.

The compound exhibited the following phase behaviour: C 99° C. N 130.5° C. I and has an extrapolated clearing point of 148° C., and at 20° C. an extrapolated birefringence of 0.153 and an extrapolated dielectric anisotropy of −16.7.

Examples 361b and 362 to 390

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence T*(N,I)/ No. R¹ R² T/° C. Δε* ° C. 361b CH₃ CH₃ 362 CH₃ C₂H₅ 363 CH₃ n-C₃H₇ 364 C₂H₅ CH₃ 365 C₂H₅ C₂H₅ 366 C₂H₅ n-C₃H₇ 367 n-C₃H₇ CH₃ 368 n-C₃H₇ C₂H₅ 369 n-C₃H₇ n-C₃H₇ 370 n-C₃H₇ n-C₅H₁₁ 371 n-C₅H₁₁ n-C₃H₇ 372 n-C₅H₁₁ n-C₅H₁₁ 373 CH₂═CH CH₃ 374 CH₂═CH C₂H₅ 375 CH₂═CH n-C₃H₇ 376 CH₂═CH CH₂═CH 377 CH₃ CH₂═CH 378 C₂H₅ CH₂═CH 379 n-C₃H₇ CH₂═CH 380 E-CH₃—CH═CH CH₂═CH 381 E-CH₃—CH═CH E-CH₃—CH═CH 382 CH₃ CH₃O 383 CH₃ C₂H₅O 384 CH₃ n-C₃H₇O 385 n-C₃H₇ CH₃O 386 n-C₃H₇ C₂H₅O 387 n-C₃H₇ n-C₃H₇O 361a n-C₅H₁₁ n-C₄H₉O C 99 N 130.5 I −16.7 148 388a n-C₄H₉O n-C₅H₁₁ 388b CH₃O CH₃O 389 C₂H₅O C₂H₅O 390 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 391 to 420

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 391 CH₃ CH₃ 392 CH₃ C₂H₅ 393 CH₃ n-C₃H₇ 394 C₂H₅ CH₃ 395 C₂H₅ C₂H₅ 396 C₂H₅ n-C₃H₇ 397 n-C₃H₇ CH₃ 398 n-C₃H₇ C₂H₅ 399 n-C₃H₇ n-C₃H₇ 400 n-C₃H₇ n-C₅H₁₁ 401 n-C₅H₁₁ n-C₃H₇ 402 n-C₅H₁₁ n-C₅H₁₁ 403 CH₂═CH CH₃ 404 CH₂═CH C₂H₅ 405 CH₂═CH n-C₃H₇ 406 CH₂═CH CH₂═CH 407 CH₃ CH₂═CH 408 C₂H₅ CH₂═CH 409 n-C₃H₇ CH₂═CH 410 E-CH₃—CH═CH CH₂═CH 411 E-CH₃—CH═CH E-CH₃—CH═CH 412 CH₃ CH₃O 413 CH₃ C₂H₅O 414 CH₃ n-C₃H₇O 415 n-C₃H₇ CH₃O 416 n-C₃H₇ C₂H₅O 417a n-C₃H₇ n-C₃H₇O 417b n-C₅H₁₁ n-C₄H₉O 417c n-C₄H₉O n-C₅H₁₁ 418 CH₃O CH₃O 419 C₂H₅O C₂H₅O 420 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 421 to 450

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 421 CH₃ CH₃ 422 CH₃ C₂H₅ 423 CH₃ n-C₃H₇ 424 C₂H₅ CH₃ 425 C₂H₅ C₂H₅ 426 C₂H₅ n-C₃H₇ 427 n-C₃H₇ CH₃ 428 n-C₃H₇ C₂H₅ 429 n-C₃H₇ n-C₃H₇ 430 n-C₃H₇ n-C₅H₁₁ 431 n-C₅H₁₁ n-C₃H₇ 432 n-C₅H₁₁ n-C₅H₁₁ 453 CH₂═CH CH₃ 434 CH₂═CH C₂H₅ 435 CH₂═CH n-C₃H₇ 436 CH₂═CH CH₂═CH 437 CH₃ CH₂═CH 438 C₂H₅ CH₂═CH 439 n-C₃H₇ CH₂═CH 440 E-CH₃—CH═CH CH₂═CH 441 E-CH₃—CH═CH E-CH₃—CH═CH 442 CH₃ CH₃O 443 CH₃ C₂H₅O 444 CH₃ n-C₃H₇O 445 n-C₃H₇ CH₃O 446 n-C₃H₇ C₂H₅O 447a n-C₃H₇ n-C₃H₇O 447b n-C₅H₁₁ n-C₄H₉O 447c n-C₄H₉O n-C₅H₁₁ 448 CH₃O CH₃O 449 C₂H₅O C₂H₅O 450 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792.

Examples 451 to 480

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 451 CH₃ CH₃ 452 CH₃ C₂H₅ 453 CH₃ n-C₃H₇ 454 C₂H₅ CH₃ 455 C₂H₅ C₂H₅ 456 C₂H₅ n-C₃H₇ 457 n-C₃H₇ CH₃ 458 n-C₃H₇ C₂H₅ 459 n-C₃H₇ n-C₃H₇ 460 n-C₃H₇ n-C₅H₁₁ 461 n-C₅H₁₁ n-C₃H₇ 462 n-C₅H₁₁ n-C₅H₁₁ 463 CH₂═CH CH₃ 464 CH₂═CH C₂H₅ 465 CH₂═CH n-C₃H₇ 466 CH₂═CH CH₂═CH 467 CH₃ CH₂═CH 468 C₂H₅ CH₂═CH 469 n-C₃H₇ CH₂═CH 470 E-CH₃—CH═CH CH₂═CH 471 E-CH₃—CH═CH E-CH₃—CH═CH 472 CH₃ CH₃O 473 CH₃ C₂H₅O 474 CH₃ n-C₃H₇O 475 n-C₃H₇ CH₃O 476 n-C₃H₇ C₂H₅O 477a n-C₃H₇ n-C₃H₇O 477b n-C₅H₁₁ n-C₄H₉O 477c n-C₄H₉O n-C₅H₁₁ 478 CH₃O CH₃O 479 C₂H₅O C₂H₅O 480 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 481 to 510

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 481 CH₃ CH₃ 482 CH₃ C₂H₅ 483 CH₃ n-C₃H₇ 484 C₂H₅ CH₃ 485 C₂H₅ C₂H₅ 486 C₂H₅ n-C₃H₇ 487 n-C₃H₇ CH₃ 488 n-C₃H₇ C₂H₅ 489 n-C₃H₇ n-C₃H₇ 490 n-C₃H₇ n-C₅H₁₁ 491 n-C₅H₁₁ n-C₃H₇ 492 n-C₅H₁₁ n-C₅H₁₁ 493 CH₂═CH CH₃ 494 CH₂═CH C₂H₅ 495 CH₂═CH n-C₃H₇ 496 CH₂═CH CH₂═CH 497 CH₃ CH₂═CH 498 C₂H₅ CH₂═CH 499 n-C₃H₇ CH₂═CH 500 E-CH₃—CH═CH CH₂═CH 501 E-CH₃—CH═CH E-CH₃—CH═CH 502 CH₃ CH₃O 503 CH₃ C₂H₅O 504 CH₃ n-C₃H₇O 505 n-C₃H₇ CH₃O 506 n-C₃H₇ C₂H₅O 507a n-C₃H₇ n-C₃H₇O 507b n-C₅H₁₁ n-C₄H₉O 507c n-C₄H₉O n-C₅H₁₁ 508 CH₃O CH₃O 509 C₂H₅O C₂H₅O 510 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 511 to 540

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 511 CH₃ CH₃ 512 CH₃ C₂H₅ 513 CH₃ n-C₃H₇ 514 C₂H₅ CH₃ 515 C₂H₅ C₂H₅ 516 C₂H₅ n-C₃H₇ 517 n-C₃H₇ CH₃ 518 n-C₃H₇ C₂H₅ 519 n-C₃H₇ n-C₃H₇ 520 n-C₃H₇ n-C₅H₁₁ 521 n-C₅H₁₁ n-C₃H₇ 522 n-C₅H₁₁ n-C₅H₁₁ 523 CH₂═CH CH₃ 524 CH₂═CH C₂H₅ 525 CH₂═CH n-C₃H₇ 526 CH₂═CH CH₂═CH 527 CH₃ CH₂═CH 528 C₂H₅ CH₂═CH 529 n-C₃H₇ CH₂═CH 530 E-CH₃—CH═CH CH₂═CH 531 E-CH₃—CH═CH E-CH₃—CH═CH 532 CH₃ CH₃O 533 CH₃ C₂H₅O 534 CH₃ n-C₃H₇O 535 n-C₃H₇ CH₃O 536 n-C₃H₇ C₂H₅O 537a n-C₃H₇ n-C₃H₇O 537b n-C₅H₁₁ n-C₄H₉O 537c n-C₄H₉O n-C₅H₁₁ 538 CH₃O CH₃O 539 C₂H₅O C₂H₅O 540 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 541 to 570

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 541 CH₃ CH₃ 542 CH₃ C₂H₅ 543 CH₃ n-C₃H₇ 544 C₂H₅ CH₃ 545 C₂H₅ C₂H₅ 546 C₂H₅ n-C₃H₇ 547 n-C₃H₇ CH₃ 548 n-C₃H₇ C₂H₅ 549 n-C₃H₇ n-C₃H₇ 550 n-C₃H₇ n-C₅H₁₁ 551 n-C₅H₁₁ n-C₃H₇ 552 n-C₅H₁₁ n-C₅H₁₁ 553 CH₂═CH CH₃ 554 CH₂═CH C₂H₅ 555 CH₂═CH n-C₃H₇ 556 CH₂═CH CH₂═CH 557 CH₃ CH₂═CH 558 C₂H₅ CH₂═CH 559 n-C₃H₇ CH₂═CH 560 E-CH₃—CH═CH CH₂═CH 561 E-CH₃—CH═CH E-CH₃—CH═CH 562 CH₃ CH₃O 563 CH₃ C₂H₅O 564 CH₃ n-C₃H₇O 565 n-C₃H₇ CH₃O 566 n-C₃H₇ C₂H₅O 567a n-C₃H₇ n-C₃H₇O 567b n-C₅H₁₁ n-C₄H₉O 567c n-C₄H₉O n-C₅H₁₁ 568 CH₃O CH₃O 569 C₂H₅O C₂H₅O 570 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 571 to 600

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 571 CH₃ CH₃ 572 CH₃ C₂H₅ 573 CH₃ n-C₃H₇ 574 C₂H₅ CH₃ 575 C₂H₅ C₂H₅ 576 C₂H₅ n-C₃H₇ 577 n-C₃H₇ CH₃ 578 n-C₃H₇ C₂H₅ 579 n-C₃H₇ n-C₃H₇ 580 n-C₃H₇ n-C₅H₁₁ 581 n-C₅H₁₁ n-C₃H₇ 582 n-C₅H₁₁ n-C₅H₁₁ 583 CH₂═CH CH₃ 584 CH₂═CH C₂H₅ 585 CH₂═CH n-C₃H₇ 586 CH₂═CH CH₂═CH 587 CH₃ CH₂═CH 588 C₂H₅ CH₂═CH 589 n-C₃H₇ CH₂═CH 590 E-CH₃—CH═CH CH₂═CH 591 E-CH₃—CH═CH E-CH₃—CH═CH 592 CH₃ CH₃O 593 CH₃ C₂H₅O 594 CH₃ n-C₃H₇O 595 n-C₃H₇ CH₃O 596 n-C₃H₇ C₂H₅O 597a n-C₃H₇ n-C₃H₇O 597b n-C₅H₁₁ n-C₄H₉O 597c n-C₄H₉O n-C₅H₁₁ 598 CH₃O CH₃O 599 C₂H₅O C₂H₅O 600 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 601 to 630

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 601 CH₃ CH₃ 602 CH₃ C₂H₅ 603 CH₃ n-C₃H₇ 604 C₂H₅ CH₃ 605 C₂H₅ C₂H₅ 606 C₂H₅ n-C₃H₇ 607 n-C₃H₇ CH₃ 608 n-C₃H₇ C₂H₅ 609 n-C₃H₇ n-C₃H₇ 610 n-C₃H₇ n-C₅H₁₁ 611 n-C₅H₁₁ n-C₃H₇ 612 n-C₅H₁₁ n-C₅H₁₁ 613 CH₂═CH CH₃ 614 CH₂═CH C₂H₅ 615 CH₂═CH n-C₃H₇ 616 CH₂═CH CH₂═CH 617 CH₃ CH₂═CH 618 C₂H₅ CH₂═CH 619 n-C₃H₇ CH₂═CH 620 E-CH₃—CH═CH CH₂═CH 621 E-CH₃—CH═CH E-CH₃—CH═CH 622 CH₃ CH₃O 623 CH₃ C₂H₅O 624 CH₃ n-C₃H₇O 625 n-C₃H₇ CH₃O 626 n-C₃H₇ C₂H₅O 627a n-C₃H₇ n-C₃H₇O 627b n-C₅H₁₁ n-C₄H₉O 527c n-C₄H₉O n-C₅H₁₁ 628 CH₃O CH₃O 629 C₂H₅O C₂H₅O 630 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 631 to 660

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 631 CH₃ CH₃ 632 CH₃ C₂H₅ 633 CH₃ n-C₃H₇ 634 C₂H₅ CH₃ 635 C₂H₅ C₂H₅ 636 C₂H₅ n-C₃H₇ 637 n-C₃H₇ CH₃ 638 n-C₃H₇ C₂H₅ 639 n-C₃H₇ n-C₃H₇ 640 n-C₃H₇ n-C₅H₁₁ 641 n-C₅H₁₁ n-C₃H₇ 642 n-C₅H₁₁ n-C₅H₁₁ 643 CH₂═CH CH₃ 644 CH₂═CH C₂H₅ 645 CH₂═CH n-C₃H₇ 646 CH₂═CH CH₂═CH 677 CH₃ CH₂═CH 648 C₂H₅ CH₂═CH 649 n-C₃H₇ CH₂═CH 650 E-CH₃—CH═CH CH₂═CH 651 E-CH₃—CH═CH E-CH₃—CH═CH 652 CH₃ CH₃O 653 CH₃ C₂H₅O 654 CH₃ n-C₃H₇O 655 n-C₃H₇ CH₃O 656 n-C₃H₇ C₂H₅O 657a n-C₃H₇ n-C₃H₇O 657b n-C₅H₁₁ n-C₄H₉O 5617c n-C₄H₉O n-C₅H₁₁ 658 CH₃O CH₃O 659 C₂H₅O C₂H₅O 660 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 661 to 690

The following are prepared analogously to Example 241 and Example

Phase sequence No. R¹ R² T/° C. Δε* 661 CH₃ CH₃ 662 CH₃ C₂H₅ 663 CH₃ n-C₃H₇ 664 C₂H₅ CH₃ 665 C₂H₅ C₂H₅ 666 C₂H₅ n-C₃H₇ 667 n-C₃H₇ CH₃ 668 n-C₃H₇ C₂H₅ 669 n-C₃H₇ n-C₃H₇ 670 n-C₃H₇ n-C₅H₁₁ 671 n-C₅H₁₁ n-C₃H₇ 672 n-C₅H₁₁ n-C₅H₁₁ 673 CH₂═CH CH₃ 674 CH₂═CH C₂H₅ 675 CH₂═CH n-C₃H₇ 676 CH₂═CH CH₂═CH 677 CH₃ CH₂═CH 678 C₂H₅ CH₂═CH 679 n-C₃H₇ CH₂═CH 680 E-CH₃—CH═CH CH₂═CH 681 E-CH₃—CH═CH E-CH₃—CH═CH 682 CH₃ CH₃O 683 CH₃ C₂H₅O 684 CH₃ n-C₃H₇O 685 n-C₃H₇ CH₃O 686 n-C₃H₇ C₂H₅O 687a n-C₃H₇ n-C₃H₇O 687b n-C₅H₁₁ n-C₄H₉O 687c n-C₄H₉O n-C₅H₁₁ 688 CH₃O CH₃O 689 C₂H₅O C₂H₅O 690 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 691 to 720 The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 691 CH₃ CH₃ 692 CH₃ C₂H₅ 693 CH₃ n-C₃H₇ 694 C₂H₅ CH₃ 695 C₂H₅ C₂H₅ 696 C₂H₅ n-C₃H₇ 697 n-C₃H₇ CH₃ 698 n-C₃H₇ C₂H₅ 699 n-C₃H₇ n-C₃H₇ 700 n-C₃H₇ n-C₅H₁₁ 701 n-C₅H₁₁ n-C₃H₇ 702 n-C₅H₁₁ n-C₅H₁₁ 703 CH₂═CH CH₃ 704 CH₂═CH C₂H₅ 705 CH₂═CH n-C₃H₇ 706 CH₂═CH CH₂═CH 707 CH₃ CH₂═CH 708 C₂H₅ CH₂═CH 709 n-C₃H₇ CH₂═CH 710 E-CH₃—CH═CH CH₂═CH 711 E-CH₃—CH═CH E-CH₃—CH═CH 712 CH₃ CH₃O 713 CH₃ C₂H₅O 714 CH₃ n-C₃H₇O 715 n-C₃H₇ CH₃O 716 n-C₃H₇ C₂H₅O 717a n-C₃H₇ n-C₃H₇O 717b n-C₅H₁₁ n-C₄H₉O 717c n-C₄H₉O n-C₅H₁₁ 718 CH₃O CH₃O 719 C₂H₅O C₂H₅O 720 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 721 to 750

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 721 CH₃ CH₃ 722 CH₃ C₂H₅ 723 CH₃ n-C₃H₇ 724 C₂H₅ CH₃ 725 C₂H₅ C₂H₅ 726 C₂H₅ n-C₃H₇ 727 n-C₃H₇ CH₃ 728 n-C₃H₇ C₂H₅ 729 n-C₃H₇ n-C₃H₇ 730 n-C₃H₇ n-C₅H₁₁ 731 n-C₅H₁₁ n-C₃H₇ 732 n-C₅H₁₁ n-C₅H₁₁ 733 CH₂═CH CH₃ 734 CH₂═CH C₂H₅ 735 CH₂═CH n-C₃H₇ 736 CH₂═CH CH₂═CH 737 CH₃ CH₂═CH 738 C₂H₅ CH₂═CH 739 n-C₃H₇ CH₂═CH 740 E-CH₃—CH═CH CH₂═CH 741 E-CH₃—CH═CH E-CH₃—CH═CH 742 CH₃ CH₃O 743 CH₃ C₂H₅O 744 CH₃ n-C₃H₇O 745 n-C₃H₇ CH₃O 746 n-C₃H₇ C₂H₅O 747a n-C₃H₇ n-C₃H₇O 747b n-C₅H₁₁ n-C₄H₉O 747c n-C₄H₉O n-C₅H₁₁ 748 CH₃O CH₃O 749 C₂H₅O C₂H₅O 750 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 751 to 780

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 751 CH₃ CH₃ 752 CH₃ C₂H₅ 753 CH₃ n-C₃H₇ 754 C₂H₅ CH₃ 755 C₂H₅ C₂H₅ 756 C₂H₅ n-C₃H₇ 757 n-C₃H₇ CH₃ 758 n-C₃H₇ C₂H₅ 759 n-C₃H₇ n-C₃H₇ 760 n-C₃H₇ n-C₅H₁₁ 761 n-C₅H₁₁ n-C₃H₇ 762 n-C₅H₁₁ n-C₅H₁₁ 763 CH₂═CH CH₃ 764 CH₂═CH C₂H₅ 765 CH₂═CH n-C₃H₇ 766 CH₂═CH CH₂═CH 767 CH₃ CH₂═CH 768 C₂H₅ CH₂═CH 769 n-C₃H₇ CH₂═CH 770 E-CH₃—CH═CH CH₂═CH 771 E-CH₃—CH═CH E-CH₃—CH═CH 772 CH₃ CH₃O 773 CH₃ C₂H₅O 774 CH₃ n-C₃H₇O 775 n-C₃H₇ CH₃O 776 n-C₃H₇ C₂H₅O 777a n-C₃H₇ n-C₃H₇O 777b n-C₅H₁₁ n-C₄H₉O 777c n-C₄H₉O n-C₅H₁₁ 778 CH₃O CH₃O 779 C₂H₅O C₂H₅O 780 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 781 to 810

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 781 CH₃ CH₃ 782 CH₃ C₂H₅ 783 CH₃ n-C₃H₇ 784 C₂H₅ CH₃ 785 C₂H₅ C₂H₅ 786 C₂H₅ n-C₃H₇ 787 n-C₃H₇ CH₃ 788 n-C₃H₇ C₂H₅ 789 n-C₃H₇ n-C₃H₇ 790 n-C₃H₇ n-C₅H₁₁ 791 n-C₅H₁₁ n-C₃H₇ 792 n-C₅H₁₁ n-C₅H₁₁ 793 CH₂═CH CH₃ 794 CH₂═CH C₂H₅ 795 CH₂═CH n-C₃H₇ 796 CH₂═CH CH₂═CH 797 CH₃ CH₂═CH 798 C₂H₅ CH₂═CH 799 n-C₃H₇ CH₂═CH 800 E-CH₃—CH═CH CH₂═CH 801 E-CH₃—CH═CH E-CH₃—CH═CH 802 CH₃ CH₃O 803 CH₃ C₂H₅O 804 CH₃ n-C₃H₇O 805 n-C₃H₇ CH₃O 806 n-C₃H₇ C₂H₅O 807a n-C₃H₇ n-C₃H₇O 807b n-C₅H₁₁ n-C₄H₉O 807c n-C₄H₉O n-C₅H₁₁ 808 CH₃O CH₃O 809 C₂H₅O C₂H₅O 810 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 811 to 840

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 811 CH₃ CH₃ 812 CH₃ C₂H₅ 813 CH₃ n-C₃H₇ 814 C₂H₅ CH₃ 815 C₂H₅ C₂H₅ 816 C₂H₅ n-C₃H₇ 817 n-C₃H₇ CH₃ 818 n-C₃H₇ C₂H₅ 819 n-C₃H₇ n-C₃H₇ 820 n-C₃H₇ n-C₅H₁₁ 821 n-C₅H₁₁ n-C₃H₇ 822 n-C₅H₁₁ n-C₅H₁₁ 823 CH₂═CH CH₃ 824 CH₂═CH C₂H₅ 825 CH₂═CH n-C₃H₇ 826 CH₂═CH CH₂═CH 827 CH₃ CH₂═CH 828 C₂H₅ CH₂═CH 829 n-C₃H₇ CH₂═CH 830 E-CH₃—CH═CH CH₂═CH 831 E-CH₃—CH═CH E-CH₃—CH═CH 832 CH₃ CH₃O 833 CH₃ C₂H₅O 834 CH₃ n-C₃H₇O 835 n-C₃H₇ CH₃O 836 n-C₃H₇ C₂H₅O 837a n-C₃H₇ n-C₃H₇O 837b n-C₅H₁₁ n-C₄H₉O 837c n-C₄H₉O n-C₅H₁₁ 838 CH₃O CH₃O 839 C₂H₅O C₂H₅O 840 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Example 841 (8-Ethoxy-4,7-difluoro-3-benzyloxybenzo[c]chromen-6-one) 841.1 Preparation of 4-bromo-1-ethoxy-2-fluorobenzene

100 g (0.524 mol) of 4-bromo-2-fluorophenol and 66.7 g (0.612 mol) of ethyl bromide were dissolved in 2 1 of ethyl methyl ketone and refluxed for 24 hours in the presence of 185 g (1.34 mol) of potassium carbonate. The solution was subsequently filtered, the filtrate was evaporated, and the crude product was filtered through silica gel with n-hexane, giving 114 g (99% of theory) of 4-bromo-1-ethoxy-2-fluorobenzene as a colourless liquid.

841.2 Preparation of 6-bromo-3-ethoxy-2-fluorobenzoic acid

Analogously to the synthesis described above (under Example 1.3), 236 g of 4-bromo-1-ethoxy-2-fluorobenzene gave 190 g (64% of theory) of 6-bromo-3-ethoxy-2-fluorobenzoic acid as colourless crystals.

841.3 Preparation of 1-benzyloxy-4-bromo-2-fluorobenzene

Analogously to the synthesis described above (under Example 2.1 or 872.1), 250 g (1.31 mol) of 4-bromo-2-fluorophenol and 179 ml (1.51 mol) of benzyl bromide gave 366 g (97%) of 1-benzyloxy-4-bromo-2-fluorobenzene as colourless crystals.

841.4 Preparation of 3-benzyloxy-6-bromo-2-fluorophenol

Analogously to the synthesis described above (under Example 1.2), 366 g (1.27 mol) of 1-benzyloxy-4-bromo-2-fluorobenzene give 270 g (72% of theory) of 3-benzyloxy-6-bromo-2-fluorophenol as colourless crystals.

841.5 Preparation of 3-benzyloxy-6-bromo-2-fluorophenyl 6-bromo-3-ethoxy-2-fluorobenzoate

Analogously to the synthesis described above (under Example 1.4), 253 g (0.851 mol) of 3-benzyloxy-6-bromo-2-fluorophenol and 246 g (0.936 mol) of 6-bromo-3-ethoky-2-fluorobenzoic acid give 405 g (87% of theory) of 3-benzyloxy-6-bromo-2-fluorophenyl 6-bromo-3-ethoxy-2-fluorobenzoate as colourless crystals.

841.6 Preparation of 8-ethoxy-4,7-difluoro-3-benzyloxybenzo[c]chromen-6-one

103 g (0.188 mol) of 3-benzyloxy-6-bromo-2-fluorophenyl 6-bromo-3-ethoxy-2-fluorobenzoate were dissolved in 1 l of DMF and refluxed for 72 hours in the presence of 119 g (1.88 mol) of copper powder. The batch was subsequently diluted with water and extracted with ethyl acetate, and the combined extracts were dried over sodium sulfate and evaporated. Crystallisation of the crude product from THF gave 15 g (21 % of theory) of 8-ethoxy-4,7-difluoro-3-benzyloxybenzo[c]chromen-6-one as pale-yellow crystals.

Examples 842 to 881

The following are prepared analogously to Example 841:

Phase sequence T*(N,I)/ No. R¹ R² T/° C. Δε* ° C. 842 CH₃ CH₃ 843 CH₃ C₂H₅ 844 CH₃ n-C₃H₇ 845 C₂H₅ CH₃ 846 C₂H₅ C₂H₅ 847 C₂H₅ n-C₃H₇ 848 n-C₃H₇ CH₃ 849 n-C₃H₇ C₂H₅ 850 n-C₃H₇ n-C₃H₇ 851 n-C₃H₇ n-C₅H₁₁ 852 n-C₅H₁₁ n-C₃H₇ 853 n-C₅H₁₁ n-C₅H₁₁ 854 CH₂═CH CH₃ 855 CH₂═CH C₂H₅ 856 CH₂═CH n-C₃H₇ 857 CH₂═CH CH₂═CH 858 CH₃ CH₂═CH 859 C₂H₅ CH₂═CH 860 n-C₃H₇ CH₂═CH 861 E-CH₃—CH═CH CH₂═CH 862 E-CH₃—CH═CH E-CH₃—CH═CH 863 CH₃ CH₃O 864 CH₃ C₂H₅O 865 CH₃ n-C₃H₇O 866 n-C₃H₇ CH₃O 867 n-C₃H₇ C₂H₅O 868a n-C₃H₇ n-C₃H₇O 868b n-C₅H₁₁ n-C₄H₉O 868c n-C₄H₉O n-C₅H₁₁ 869 CH₃O CH₃O 841 C₂H₅O H 870 C₂H₅O C₂H₅O 871 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Example 872 (8-Ethoxy-4,7-difluoro-3-(trans-4-vinylcyclohexylmethoxy)-6H-benzo[c]chromene) 872.1 Preparation of 8-ethoxy-4,7-difluoro-3-hydroxy-6H-benzo[c]chromene

2.00 g (5.24 mmol) of 3-benzyloxy-8-ethoxy-4,7-difluoro-6H-benzo[c]chromen-6-one, the compound of Example 841, were dissolved in 12 ml of THF, and 2.37 ml (23.0 mmol) of boron trifluoride/THF complex were added with ice-cooling. 24 ml of ethylene glycol dimethyl ether and then in portions 530 mg of sodium borohydride were subsequently added. The mixture was subsequently stirred at room temperature for 18 hours and then transferred onto ice. The mixture was subjected to conventional purification, giving 1.5 g (78% of theory) of 3-benzyloxy-8-ethoxy-4,7-difluoro-6H-benzo[c]chromene as colourless crystals. These were dissolved in THF, hydrogenated at a pressure of 1 bar in the presence of 0.6 g of Pd/C (5%), filtered and evaporated, giving 1.2 g (99% of theory) of 8-ethoxy-4,7-difluoro-3-hydroxy-6H-benzo[c]chromene as colourless crystals.

872.2 Preparation of 8-ethoxy-4,7-difluoro-3-(trans-4-vinylcyclohexyl-methoxy)-6H-benzo[c]chromene

1.2 g (4.32 mmol) of 8-ethoxy4,7-difluoro-3-hydroxy-6H-benzo[c]-chromene, 2.16 g (8.64 mmol) of (trans-4-vinylcyclohexyl)methyl iodide and 650 mg (5 mmol) of potassium carbonate were refluxed for 16 hours in 15 ml of acetone. The mixture was then -transferred into MTB ether and subjected to conventional purification, giving 460.mg (27% of theory) of 8-ethoxy-4,7-difluoro-3-(trans-4-vinylcyclohexylmethoxy)-6 H-benzo[c]-chromene as colourless crystals.

Examples 873-902

The following are prepared analogously to Example 872:

Phase sequence T*(N,I)/ No. R¹ R² T/° C. Δε* ° C. 873 CH₃ CH₃ 874 CH₃ C₂H₅ 875 CH₃ n-C₃H₇ 876 C₂H₅ CH₃ 877 C₂H₅ C₂H₅ 878 C₂H₅ n-C₃H₇ 879 n-C₃H₇ CH₃ 880 n-C₃H₇ C₂H₅ 881 n-C₃H₇ n-C₃H₇ 882 n-C₃H₇ n-C₅H₁₁ 883 n-C₅H₁₁ n-C₃H₇ 884 n-C₅H₁₁ n-C₅H₁₁ 885 CH₂═CH CH₃ 886 CH₂═CH C₂H₅ 887 CH₂═CH n-C₃H₇ 872 CH₂═CH C₂H₅O C 123 N 167 I −10.4 207 888 CH₂═CH CH₂═CH 889 CH₃ CH₂═CH 890 C₂H₅ CH₂═CH 891 n-C₃H₇ CH₂═CH 892 E-CH₃—CH═CH CH₂═CH 893 E-CH₃—CH═CH E-CH₃—CH═CH 894 CH₃ CH₃O 895 CH₃ C₂H₅O 896 CH₃ n-C₃H₇O 897 n-C₃H₇ CH₃O 898 n-C₃H₇ C₂H₅O 899a n-C₃H₇ n-C₃H₇O 899b n-C₅H₁₁ n-C₄H₉O C 109 SA 157 N −11.2 199 167.5 I 899c n-C₄H₉O n-C₅H₁₁ 900 CH₃O CH₃O 901 C₂H₅O C₂H₅O 902 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 903 to 934

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 903 CH₃ CH₃ 904 CH₃ C₂H₅ 905 CH₃ n-C₃H₇ 906 C₂H₅ CH₃ 907 C₂H₅ C₂H₅ 908 C₂H₅ n-C₃H₇ 909 n-C₃H₇ CH₃ 910 n-C₃H₇ C₂H₅ 911 n-C₃H₇ n-C₃H₇ 912 n-C₃H₇ n-C₅H₁₁ 913 n-C₅H₁₁ n-C₃H₇ 914 n-C₅H₁₁ n-C₅H₁₁ 915 CH₂═CH CH₃ 916 CH₂═CH C₂H₅ 917 CH₂═CH n-C₃H₇ 918 CH₂═CH CH₂═CH 919 CH₃ CH₂═CH 920 C₂H₅ CH₂═CH 921 n-C₃H₇ CH₂═CH 922 E-CH₃—CH═CH CH₂═CH 923 E-CH₃—CH═CH E-CH₃—CH═CH 924 CH₃ CH₃O 925 CH₃ C₂H₅O 926 CH₃ n-C₃H₇O 927 n-C₃H₇ CH₃O 928 n-C₃H₇ C₂H₅O 929 n-C₃H₇ n-C₃H₇O 930 n-C₅H₁₁ n-C₄H₉O 931 n-C₄H₉O n-C₅H₁₁ 932 CH₃O CH₃O 933 C₂H₅O C₂H₅O 934 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 935 to 966

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 935 CH₃ CH₃ 936 CH₃ C₂H₅ 937 CH₃ n-C₃H₇ 938 C₂H₅ CH₃ 939 C₂H₅ C₂H₅ 940 C₂H₅ n-C₃H₇ 941 n-C₃H₇ CH₃ 942 n-C₃H₇ C₂H₅ 943 n-C₃H₇ n-C₃H₇ 944 n-C₃H₇ n-C₅H₁₁ 945 n-C₅H₁₁ n-C₃H₇ 946 n-C₅H₁₁ n-C₅H₁₁ 947 CH₂═CH CH₃ 948 CH₂═CH C₂H₅ 949 CH₂═CH n-C₃H₇ 950 CH₂═CH CH₂═CH 951 CH₃ CH₂═CH 952 C₂H₅ CH₂═CH 953 n-C₃H₇ CH₂═CH 954 E-CH₃—CH═CH CH₂═CH 955 E-CH₃—CH═CH E-CH₃—CH═CH 956 CH₃ CH₃O 957 CH₃ C₂H₅O 958 CH₃ n-C₃H₇O 959 n-C₃H₇ CH₃O 960 n-C₃H₇ C₂H₅O 961 n-C₃H₇ n-C₃H₇O 962 n-C₅H₁₁ n-C₄H₉O 963 n-C₄H₉O n-C₅H₁₁ 964 CH₃O CH₃O 965 C₂H₅O C₂H₅O 966 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 967 to 998

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 967 CH₃ CH₃ 968 CH₃ C₂H₅ 969 CH₃ n-C₃H₇ 970 C₂H₅ CH₃ 971 C₂H₅ C₂H₅ 972 C₂H₅ n-C₃H₇ 973 n-C₃H₇ CH₃ 974 n-C₃H₇ C₂H₅ 975 n-C₃H₇ n-C₃H₇ 976 n-C₃H₇ n-C₅H₁₁ 977 n-C₅H₁₁ n-C₃H₇ 978 n-C₅H₁₁ n-C₅H₁₁ 979 CH₂═CH CH₃ 980 CH₂═CH C₂H₅ 981 CH₂═CH n-C₃H₇ 982 CH₂═CH CH₂═CH 983 CH₃ CH₂═CH 984 C₂H₅ CH₂═CH 985 n-C₃H₇ CH₂═CH 986 E-CH₃—CH═CH CH₂═CH 987 E-CH₃—CH═CH E-CH₃—CH═CH 988 CH₃ CH₃O 989 CH₃ C₂H₅O 990 CH₃ n-C₃H₇O 991 n-C₃H₇ CH₃O 992 n-C₃H₇ C₂H₅O 993 n-C₃H₇ n-C₃H₇O 994 n-C₅H₁₁ n-C₄H₉O 995 n-C₄H₉O n-C₅H₁₁ 996 CH₃O CH₃O 997 C₂H₅O C₂H₅O 998 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 999 to 1030

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε*  999 CH₃ CH₃ 1000 CH₃ C₂H₅ 1001 CH₃ n-C₃H₇ 1002 C₂H₅ CH₃ 1003 C₂H₅ C₂H₅ 1004 C₂H₅ n-C₃H₇ 1005 n-C₃H₇ CH₃ 1006 n-C₃H₇ C₂H₅ 1007 n-C₃H₇ n-C₃H₇ 1008 n-C₃H₇ n-C₅H₁₁ 1009 n-C₅H₁₁ n-C₃H₇ 1010 n-C₅H₁₁ n-C₅H₁₁ 1011 CH₂═CH CH₃ 1012 CH₂═CH C₂H₅ 1013 CH₂═CH n-C₃H₇ 1014 CH₂═CH CH₂═CH 1015 CH₃ CH₂═CH 1016 C₂H₅ CH₂═CH 1017 n-C₃H₇ CH₂═CH 1018 E-CH₃—CH═CH CH₂═CH 1019 E-CH₃—CH═CH E-CH₃—CH═CH 1020 CH₃ CH₃O 1021 CH₃ C₂H₅O 1022 CH₃ n-C₃H₇O 1023 n-C₃H₇ CH₃O 1024 n-C₃H₇ C₂H₅O 1025 n-C₃H₇ n-C₃H₇O 1026 n-C₅H₁₁ n-C₄H₉O C 187 S_(A) 230 N 230.4 I 1027 n-C₄H₉O n-C₅H₁₁ 1028 CH₃O CH₃O 1029 C₂H₅O C₂H₅O 1030 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1031 to 1062

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 1031 CH₃ CH₃ 1032 CH₃ C₂H₅ 1033 CH₃ n-C₃H₇ 1034 C₂H₅ CH₃ 1035 C₂H₅ C₂H₅ 1036 C₂H₅ n-C₃H₇ 1037 n-C₃H₇ CH₃ 1038 n-C₃H₇ C₂H₅ 1039 n-C₃H₇ n-C₃H₇ 1040 n-C₃H₇ n-C₅H₁₁ 1041 n-C₅H₁₁ n-C₃H₇ 1042 n-C₅H₁₁ n-C₅H₁₁ 1043 CH₂═CH CH₃ 1044 CH₂═CH C₂H₅ 1045 CH₂═CH n-C₃H₇ 1046 CH₂═CH CH₂═CH 1047 CH₃ CH₂═CH 1048 C₂H₅ CH₂═CH 1049 n-C₃H₇ CH₂═CH 1050 E-CH₃—CH═CH CH₂═CH 1051 E-CH₃—CH═CH E-CH₃—CH═CH 1052 CH₃ CH₃O 1053 CH₃ C₂H₅O 1054 CH₃ n-C₃H₇O 1055 n-C₃H₇ CH₃O 1056 n-C₃H₇ C₂H₅O 1057 n-C₃H₇ n-C₃H₇O 1058 n-C₅H₁₁ n-C₅H₁₁O C 151 S_(B) 188 S_(A) 191 I 1059 n-C₄H₉O n-C₅H₁₁ 1060 CH₃O CH₃O 1061 C₂H₅O C₂H₅O 1062 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1063 to 1093

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 1063 CH₃ CH₃ 1064 CH₃ C₂H₅ 1065 CH₃ n-C₃H₇ 1066 C₂H₅ CH₃ 1067 C₂H₅ C₂H₅ 1068 C₂H₅ n-C₃H₇ 1069 n-C₃H₇ CH₃ 1070 n-C₃H₇ C₂H₅ 1071 n-C₃H₇ n-C₃H₇ 1072 n-C₃H₇ n-C₅H₁₁ 1073 n-C₅H₁₁ n-C₃H₇ 1074 n-C₅H₁₁ n-C₅H₁₁ 1075 CH₂═CH CH₃ 1076 CH₂═CH C₂H₅ 1077 CH₂═CH n-C₃H₇ 1078 CH₂═CH CH₂═CH 1079 CH₃ CH₂═CH 1080 C₂H₅ CH₂═CH 1081 n-C₃H₇ CH₂═CH 1082 E-CH₃—CH═CH CH₂═CH 1083 E-CH₃—CH═CH E-CH₃—CH═CH 1084 CH₃ CH₃O 1085 CH₃ C₂H₅O 1086 CH₃ n-C₃H₇O 1087 n-C₃H₇ CH₃O 1088 n-C₃H₇ C₂H₅O 1089 n-C₃H₇ n-C₃H₇O 1090 n-C₄H₉O n-C₅H₁₁ 1091 CH₃O CH₃O 1092 C₂H₅O C₂H₅O 1093 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1094 to 1125

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 1094 CH₃ CH₃ 1095 CH₃ C₂H₅ 1096 CH₃ n-C₃H₇ 1097 C₂H₅ CH₃ 1098 C₂H₅ C₂H₅ 1099 C₂H₅ n-C₃H₇ 1100 n-C₃H₇ CH₃ 1101 n-C₃H₇ C₂H₅ 1102 n-C₃H₇ n-C₃H₇ 1103 n-C₃H₇ n-C₅H₁₁ 1104 n-C₅H₁₁ n-C₃H₇ 1105 n-C₅H₁₁ n-C₅H₁₁ 1106 CH₂═CH CH₃ 1107 CH₂═CH C₂H₅ 1108 CH₂═CH n-C₃H₇ 1109 CH₂═CH CH₂═CH 1110 CH₃ CH₂═CH 1111 C₂H₅ CH₂═CH 1112 n-C₃H₇ CH₂═CH 1113 E-CH₃—CH═CH CH₂═CH 1114 E-CH₃—CH═CH E-CH₃—CH═CH 1115 CH₃ CH₃O 1116 CH₃ C₂H₅O 1117 CH₃ n-C₃H₇O 1118 n-C₃H₇ CH₃O 1119 n-C₃H₇ C₂H₅O 1120 n-C₃H₇ n-C₃H₇O 1121 n-C₅H₁₁ n-C₄H₉O 1122 n-C₄H₉O n-C₅H₁₁ 1123 CH₃O CH₃O 1124 C₂H₅O C₂H₅O 1125 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1126 to 1157

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 1126 CH₃ CH₃ 1127 CH₃ C₂H₅ 1128 CH₃ n-C₃H₇ 1129 C₂H₅ CH₃ 1130 C₂H₅ C₂H₅ 1131 C₂H₅ n-C₃H₇ 1132 n-C₃H₇ CH₃ 1133 n-C₃H₇ C₂H₅ 1134 n-C₃H₇ n-C₃H₇ 1135 n-C₃H₇ n-C₅H₁₁ 1136 n-C₅H₁₁ n-C₃H₇ 1137 n-C₅H₁₁ n-C₅H₁₁ 1138 CH₂═CH CH₃ 1139 CH₂═CH C₂H₅ 1140 CH₂═CH n-C₃H₇ 1141 CH₂═CH CH₂═CH 1142 CH₃ CH₂═CH 1143 C₂H₅ CH₂═CH 1144 n-C₃H₇ CH₂═CH 1145 E-CH₃—CH═CH CH₂═CH 1146 E-CH₃—CH═CH E-CH₃—CH═CH 1147 CH₃ CH₃O 1148 CH₃ C₂H₅O 1149 CH₃ n-C₃H₇O 1150 n-C₃H₇ CH₃O 1151 n-C₃H₇ C₂H₅O 1152 n-C₃H₇ n-C₃H₇O 1153 n-C₅H₁₁ n-C₄H₉O 1154 n-C₄H₉O n-C₅H₁₁ 1155 CH₃O CH₃O 1156 C₂H₅O C₂H₅O 1157 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1158 to 1190

The following are prepared analogously to Example 241 and Example 361 a:

Phase sequence No. R¹ R² T/° C. Δε* 1158 CH₃ CH₃ 1159 CH₃ C₂H₅ 1160 CH₃ n-C₃H₇ 1161 C₂H₅ CH₃ 1162 C₂H₅ C₂H₅ 1163 C₂H₅ n-C₃H₇ 1154 n-C₃H₇ CH₃ 1165 n-C₃H₇ C₂H₅ 1166 n-C₃H₇ n-C₃H₇ 1167 n-C₃H₇ n-C₅H₁₁ 1168 n-C₅H₁₁ n-C₃H₇ 1159 n-C₅H₁₁ n-C₅H₁₁ 1170 CH₂═CH CH₃ 1171 CH₂═CH C₂H₅ 1172 CH₂═CH n-C₃H₇ 1173 CH₂═CH CH₂═CH 1174 CH₃ CH₂═CH 1175 C₂H₅ CH₂═CH 1176 n-C₃H₇ CH₂═CH 1177 E-CH₃—CH═CH CH₂═CH 1178 E-CH₃—CH═CH E-CH₃—CH═CH 1179 CH₃ CH₃O 1180 CH₃ C₂H₅O 1181 CH₃ n-C₃H₇O 1182 n-C₃H₇ CH₃O 1183 n-C₃H₇ C₂H₅O 1184 n-C₃H₇ n-C₃H₇O 1185 n-C₅H₁₁ n-C₄H₉O 1186 n-C₄H₉O n-C₅H₁₁ 1187 CH₃O CH₃O 1188 C₂H₅O C₂H₅O 1190 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1191 to 1222

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 1191 CH₃ CH₃ 1192 CH₃ C₂H₅ 1193 CH₃ n-C₃H₇ 1194 C₂H₅ CH₃ 1195 C₂H₅ C₂H₅ 1196 C₂H₅ n-C₃H₇ 1197 n-C₃H₇ CH₃ 1198 n-C₃H₇ C₂H₅ 1199 n-C₃H₇ n-C₃H₇ 1200 n-C₃H₇ n-C₅H₁₁ 1201 n-C₅H₁₁ n-C₃H₇ 1202 n-C₅H₁₁ n-C₅H₁₁ 1203 CH₂═CH CH₃ 1204 CH₂═CH C₂H₅ 1205 CH₂═CH n-C₃H₇ 1206 CH₂═CH CH₂═CH 1207 CH₃ CH₂═CH 1208 C₂H₅ CH₂═CH 1209 n-C₃H₇ CH₂═CH 1200 E-CH₃—CH═CH CH₂═CH 1211 E-CH₃—CH═CH E-CH₃—CH═CH 1212 CH₃ CH₃O 1213 CH₃ C₂H₅O 1214 CH₃ n-C₃H₇O 1215 n-C₃H₇ CH₃O 1216 n-C₃H₇ C₂H₅O 1217 n-C₃H₇ n-C₃H₇O 1218 n-C₅H₁₁ n-C₄H₉O 1219 n-C₄H₉O n-C₅H₁₁ 1220 CH₃O CH₃O 1221 C₂H₅O C₂H₅O 1222 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1223 to 1254

The following are prepared analogously to Example 241 and Example 361a;

Phase sequence No. R¹ R² T/° C. Δε* 1223 CH₃ CH₃ 1224 CH₃ C₂H₅ 1225 CH₃ n-C₃H₇ 1226 C₂H₅ CH₃ 1227 C₂H₅ C₂H₅ 1228 C₂H₅ n-C₃H₇ 1229 n-C₃H₇ CH₃ 1230 n-C₃H₇ C₂H₅ 1231 n-C₃H₇ n-C₃H₇ 1232 n-C₃H₇ n-C₅H₁₁ 1233 n-C₅H₁₁ n-C₃H₇ 1234 n-C₅H₁₁ n-C₅H₁₁ 1235 CH₂═CH CH₃ 1236 CH₂═CH C₂H₅ 1237 CH₂═CH n-C₃H₇ 1238 CH₂═CH CH₂═CH 1239 CH₃ CH₂═CH 1240 C₂H₅ CH₂═CH 1241 n-C₃H₇ CH₂═CH 1242 E-CH₃—CH═CH CH₂═CH 1243 E-CH₃—CH═CH E-CH₃—CH═CH 1244 CH₃ CH₃O 1245 CH₃ C₂H₅O 1246 CH₃ n-C₃H₇O 1247 n-C₃H₇ CH₃O 1248 n-C₃H₇ C₂H₅O 1249 n-C₃H₇ n-C₃H₇O 1250 n-C₅H₁₁ n-C₄H₉O 1251 n-C₄H₉O n-C₅H₁₁ 1252 CH₃O CH₃O 1253 C₂H₅O C₂H₅O 1254 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1255 to 1286

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 1255 CH₃ CH₃ 1256 CH₃ C₂H₅ 1257 CH₃ n-C₃H₇ 1258 C₂H₅ CH₃ 1259 C₂H₅ C₂H₅ 1260 C₂H₅ n-C₃H₇ 1261 n-C₃H₇ CH₃ 1262 n-C₃H₇ C₂H₅ 1263 n-C₃H₇ n-C₃H₇ 1264 n-C₃H₇ n-C₅H₁₁ 1265 n-C₅H₁₁ n-C₃H₇ 1266 n-C₅H₁₁ n-C₅H₁₁ 1267 CH₂═CH CH₃ 1268 CH₂═CH C₂H₅ 1269 CH₂═CH n-C₃H₇ 1270 CH₂═CH CH₂═CH 1271 CH₃ CH₂═CH 1272 C₂H₅ CH₂═CH 1273 n-C₃H₇ CH₂═CH 1274 E-CH₃—CH═CH CH₂═CH 1275 E-CH₃—CH═CH E-CH₃—CH═CH 1276 CH₃ CH₃O 1277 CH₃ C₂H₅O 1278 CH₃ n-C₃H₇O 1279 n-C₃H₇ CH₃O 1280 n-C₃H₇ C₂H₅O 1281 n-C₃H₇ n-C₃H₇O 1252 n-C₅H₁₁ n-C₄H₉O 1283 n-C₄H₉O n-C₅H₁₁ 1284 CH₃O CH₃O 1285 C₂H₅O C₂H₅O 1286 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1287 to 1318

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 1287 CH₃ CH₃ 1288 CH₃ C₂H₅ 1289 CH₃ n-C₃H₇ 1290 C₂H₅ CH₃ 1291 C₂H₅ C₂H₅ 1292 C₂H₅ n-C₃H₇ 1293 n-C₃H₇ CH₃ 1294 n-C₃H₇ C₂H₅ 1295 n-C₃H₇ n-C₃H₇ 1296 n-C₃H₇ n-C₅H₁₁ 1297 n-C₅H₁₁ n-C₃H₇ 1298 n-C₅H₁₁ n-C₅H₁₁ 1299 CH₂═CH CH₃ 1300 CH₂═CH C₂H₅ 1301 CH₂═CH n-C₃H₇ 1302 CH₂═CH CH₂═CH 1303 CH₃ CH₂═CH 1304 C₂H₅ CH₂═CH 1305 n-C₃H₇ CH₂═CH 1306 E-CH₃—CH═CH CH₂═CH 1307 E-CH₃—CH═CH E-CH₃—CH═CH 1308 CH₃ CH₃O 1309 CH₃ C₂H₅O 1310 CH₃ n-C₃H₇O 1311 n-C₃H₇ CH₃O 1312 n-C₃H₇ C₂H₅O 1313 n-C₃H₇ n-C₃H₇O 1314 n-C₅H₁₁ n-C₄H₉O 1315 n-C₄H₉O n-C₅H₁₁ 1316 CH₃O CH₃O 1317 C₂H₅O C₂H₅O 1318 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1319 to 1350

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 1319 CH₃ CH₃ 1320 CH₃ C₂H₅ 1321 CH₃ n-C₃H₇ 1322 C₂H₅ CH₃ 1323 C₂H₅ C₂H₅ 1324 C₂H₅ n-C₃H₇ 1325 n-C₃H₇ CH₃ 1326 n-C₃H₇ C₂H₅ 1327 n-C₃H₇ n-C₃H₇ 1328 n-C₃H₇ n-C₅H₁₁ 1329 n-C₅H₁₁ n-C₃H₇ 1330 n-C₅H₁₁ n-C₅H₁₁ 1331 CH₂═CH CH₃ 1332 CH₂═CH C₂H₅ 1333 CH₂═CH n-C₃H₇ 1334 CH₂═CH CH₂═CH 1335 CH₃ CH₂═CH 1336 C₂H₅ CH₂═CH 1337 n-C₃H₇ CH₂═CH 1338 E-CH₃—CH═CH CH₂═CH 1339 E-CH₃—CH═CH E-CH₃—CH═CH 1340 CH₃ CH₃O 1341 CH₃ C₂H₅O 1342 CH₃ n-C₃H₇O 1343 n-C₃H₇ CH₃O 1344 n-C₃H₇ C₂H₅O 1345 n-C₃H₇ n-C₃H₇O 1346 n-C₅H₁₁ n-C₄H₉O C 112 S_(A) 149 I −8.1 1347 n-C₄H₉O n-C₅H₁₁ 1348 CH₃O CH₃O 1349 C₂H₅O C₂H₅O 1350 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1351 to 1382

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 1351 CH₃ CH₃ 1352 CH₃ C₂H₅ 1353 CH₃ n-C₃H₇ 1354 C₂H₅ CH₃ 1355 C₂H₅ C₂H₅ 1356 C₂H₅ n-C₃H₇ 1357 n-C₃H₇ CH₃ 1358 n-C₃H₇ C₂H₅ 1359 n-C₃H₇ n-C₃H₇ 1360 n-C₃H₇ n-C₅H₁₁ 1361 n-C₅H₁₁ n-C₃H₇ 1362 n-C₅H₁₁ n-C₅H₁₁ 1363 CH₂═CH CH₃ 1364 CH₂═CH C₂H₅ 1365 CH₂═CH n-C₃H₇ 1366 CH₂═CH CH₂═CH 1367 CH₃ CH₂═CH 1368 C₂H₅ CH₂═CH 1369 n-C₃H₇ CH₂═CH 1370 E-CH₃—CH═CH CH₂═CH 1371 E-CH₃—CH═CH E-CH₃—CH═CH 1372 CH₃ CH₃O 1373 CH₃ C₂H₅O 1374 CH₃ n-C₃H₇O 1375 n-C₃H₇ CH₃O 1376 n-C₃H₇ C₂H₅O 1377 n-C₃H₇ n-C₃H₇O 1378 n-C₅H₁₁ n-C₄H₉O 1379 n-C₄H₉O n-C₅H₁₁ 1380 CH₃O CH₃O 1381 C₂H₅O C₂H₅O 1382 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1383 to 1385

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 1383 CH₃ CH₃ 1384 CH₃ C₂H₅ 1385 CH₃ n-C₃H₇ 1386 C₂H₅ CH₃ 1387 C₂H₅ C₂H₅ 1388 C₂H₅ n-C₃H₇ 1389 n-C₃H₇ CH₃ 1390 n-C₃H₇ C₂H₅ 1391 n-C₃H₇ n-C₃H₇ 1392 n-C₃H₇ n-C₅H₁₁ 1393 n-C₅H₁₁ n-C₃H₇ 1394 n-C₅H₁₁ n-C₅H₁₁ 1395 CH₂═CH CH₃ 1396 CH₂═CH C₂H₅ 1397 CH₂═CH n-C₃H₇ 1398 CH₂═CH CH₂═CH 1399 CH₃ CH₂═CH 1400 C₂H₅ CH₂═CH 1401 n-C₃H₇ CH₂═CH 1402 E-CH₃—CH═CH CH₂═CH 1403 E-CH₃—CH═CH E-CH₃—CH═CH 1404 CH₃ CH₃O 1405 CH₃ C₂H₅O 1406 CH₃ n-C₃H₇O 1407 n-C₃H₇ CH₃O 1408 n-C₃H₇ C₂H₅O 1409 n-C₃H₇ n-C₃H₇O 1410 n-C₅H₁₁ n-C₄H₉O 1411 n-C₄H₉O n-C₅H₁₁ 1412 CH₃O CH₃O 1413 C₂H₅O C₂H₅O 1414 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1415 to 1446

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 1415 CH₃ CH₃ 1416 CH₃ C₂H₅ 1417 CH₃ n-C₃H₇ 1418 C₂H₅ CH₃ 1419 C₂H₅ C₂H₅ 1420 C₂H₅ n-C₃H₇ 1421 n-C₃H₇ CH₃ 1422 n-C₃H₇ C₂H₅ 1423 n-C₃H₇ n-C₃H₇ 1424 n-C₃H₇ n-C₅H₁₁ 1425 n-C₅H₁₁ n-C₃H₇ 1426 n-C₅H₁₁ n-C₅H₁₁ 1427 CH₂═CH CH₃ 1428 CH₂═CH C₂H₅ 1429 CH₂═CH n-C₃H₇ 1430 CH₂═CH CH₂═CH 1431 CH₃ CH₂═CH 1432 C₂H₅ CH₂═CH 1433 n-C₃H₇ CH₂═CH 1434 E-CH₃—CH═CH CH₂═CH 1435 E-CH₃—CH═CH E-CH₃—CH═CH 1436 CH₃ CH₃O 1437 CH₃ C₂H₅O 1438 CH₃ n-C₃H₇O 1439 n-C₃H₇ CH₃O 1440 n-C₃H₇ C₂H₅O 1441 n-C₃H₇ n-C₃H₇O 1442 n-C₅H₁₁ n-C₄H₉O 1443 n-C₄H₉O n-C₅H₁₁ 1444 CH₃O CH₃O 1445 C₂H₅O C₂H₅O 1446 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Examples 1447 to 1478

The following are prepared analogously to Example 241 and Example 361a:

Phase sequence No. R¹ R² T/° C. Δε* 1447 CH₃ CH₃ 1448 CH₃ C₂H₅ 1449 CH₃ n-C₃H₇ 1450 C₂H₅ CH₃ 1451 C₂H₅ C₂H₅ 1452 C₂H₅ n-C₃H₇ 1453 n-C₃H₇ CH₃ 1454 n-C₃H₇ C₂H₅ 1455 n-C₃H₇ n-C₃H₇ 1456 n-C₃H₇ n-C₅H₁₁ 1457 n-C₅H₁₁ n-C₃H₇ 1458 n-C₅H₁₁ n-C₅H₁₁ 1459 CH₂═CH CH₃ 1460 CH₂═CH C₂H₅ 1461 CH₂═CH n-C₃H₇ 1462 CH₂═CH CH₂═CH 1463 CH₃ CH₂═CH 1464 C₂H₅ CH₂═CH 1465 n-C₃H₇ CH₂═CH 1466 E-CH₃—CH═CH CH₂═CH 1467 E-CH₃—CH═CH E-CH₃—CH═CH 1468 CH₃ CH₃O 1469 CH₃ C₂H₅O 1470 CH₃ n-C₃H₇O 1471 n-C₃H₇ CH₃O 1472 n-C₃H₇ C₂H₅O 1473 n-C₃H₇ n-C₃H₇O 1474 n-C₅H₁₁ n-C₄H₉O 1475 n-C₄H₉O n-C₅H₁₁ 1476 CH₃O CH₃O 1477 C₂H₅O C₂H₅O 1478 n-C₃H₇O n-C₃H₇O Note *values extrapolated from 10% solution in ZLI-4792 or ZLI-2857 (Δε).

Mixture Examples

Liquid-crystalline mixtures are prepared and their applicational properties are investigated.

Example M-1

A liquid-crystal mixture having the composition indicated in the following table was prepared and investigated. It has the properties likewise shown in the table. Composition Compound Abbre- Conc./% # viation by wt. Physical properties 1 PCH-301 9.0 T(N, I) = 65.9° C. 2 PCH-302 9.0 ε⊥(20° C., 1 kHz) > 6.1 3 CCH-301 29.7 Δε(20° C., 1 kHz) > −2.3 4 CCN-47 9.9 5 CCN-55 9.0 6 CBC-33F 4.5 7 CBC-53F 4.5 8 CBC-55F 4.5 9 CBC-33 4.5 10 CBC-53 5.4 11 BFFO-3-5FF 10.0 Σ 100.0

The liquid-crystal medium has very good applicational properties.

Example M-2

A liquid-crystal mixture having the composition indicated in the following table was prepared and investigated. It has the properties likewise shown in the table. Composition Com- pound Abbre- Conc./% # viation by wt. Physical properties 1 PCH-301 9.0 T(N, I) = 76.9° C. 2 PCH-302 9.0 ε⊥(20° C., 1 kHz) > 5.4 3 CCH-301 29.7 Δε(20° C., 1 kHz) > −1.9 4 CCN-47 9.9 5 CCN-55 9.0 6 CBC-33F 4.5 7 CBC-53F 4.5 8 CBC-55F 4.5 9 CBC-33 4.5 10 CBC-53 5.4 11 BHHO-3O-5FF 10.0 Σ 100.0

The liquid-crystal medium has very good applicational properties.

Example M-3

The mixture shown in the following table is prepared and investigated. Composition Com- pound Abbre- Conc./% # viation by wt. Physical properties 1 PCH-304FF 16.0 T(N, I) = 70° C. 2 PCH-502FF 8.0 Δn(20° C., 589 nm) = 0.100 3 PCH-504FF 14.0 Δε(20° C., 1 kHz) > −4.5 4 CCP-302FF 14.0 5 CCP-502FF 12.0 6 CCH-35 6.0 7 CC-3-V1 8.0 8 CCP-V-1 8.0 9 BCH-32 8.0 10 BFFO-3-5FF 3.0 11 BHHO-20-5FF 3.0 Σ 100.0

The liquid-crystal medium has excellent applicational properties.

Example M-4

The mixture shown in the following table is prepared and investigated. Composition Com- pound Abbre- Conc./% # viation by wt. Physical properties 1 PCH-304FF 7.0 T(N, I) = 95.5° C. 2 CCP-402FF 2.0 Δn (20° C., 589 0.128 nm) = 3 CCP-303FF 7.0 Δε (20° C., 1 −3.2 kHz) > 4 BCH-202FF 11.0 k₁ (20° C.) = 16.0 pN 5 BCH-302FF 11.0 k₁/k₃ (20° C.) = 0.94 6 PYP-2-3 10.0 γ₁ (20° C.) = 154 mPa · s 7 PYP-2-4 10.0 t_(store) (−20° C.) > 1,000 h 8 CC-4-V 10.0 V₀ (20° C.) = 2.28 V 9 CC-5-V 10.0 10 CC-3-V1 10.0 11 CCP-V-1 2.0 12 CCH-34 5.0 13 C-BHHO- 3.0 5-04FF Σ 100.0

The liquid-crystal medium has excellent applicational properties, as is evident, for example,in comparison with the following comparative example (CM-1).

Comparative Example CM-1

The mixture shown in the following table, which comprises no compound according to the invention, is prepared and investigated. Composition Com- pound Abbre- Conc./% # viation by wt. Physical properties 1 PCH-304FF 12.0 T(N, I) = 96° C. 2 PCH-502FF 10.0 Δn (20° C., 589 0.126 nm) = 3 BCH-202FF 12.0 Δε (20° C., 1 −3.1 kHz) > 4 BCH-302FF 13.0 k₁ (20° C.) = 15.0 pN 5 PYP-2-3 8.0 k₁/k₃ (20° C.) = 1.09 6 PYP-2-4 8.0 γ₁ (20° C.) = 169 mPa · s 7 CC-4-V 13.0 t_(store) (−20° C.) > 1,000 h 8 CC-3-V1 9.0 V₀ (20° C.) = 2.42 V 9 CCP-V-1 10.0 10 CCPC-33 3.0 11 CCPC-34 3.0 Σ 100.0

The liquid-crystal medium has similar values for the clearing point, the birefringence and the dielectric anisotropy to the medium of Example 4. However, it has significantly higher rotational viscosity and at the same time a higher threshold voltage and consequently has clearly inferior applicational properties.

Example M-5

The mixture shown in the following table is prepared and investigated. Composition Com- pound Abbre- Conc./% # viation by wt. Physical properties 1 PCH-304FF 5.0 T(N, I) = 95.5° C. 2 PCH-502FF 3.0 Δn (20° C., 589 0.129 nm) = 3 CCP-303FF 10.0 Δε (20° C., 1 −3.8 kHz) > 4 BCH-202FF 11.0 k₁ (20° C.) = 15.7 pN 5 BCH-302FF 11.0 k₁/k₃ (20° C.) = 0.97 6 PYP-2-3 6.0 γ₁ (20° C.) = 173 mPa · s 7 PYP-2-4 14.0 t_(store) (−20° C.) > 1,000 h 8 CC-4-V 15.0 V₀ (20° C.) = 2.10 V 9 CC-3-V1 12.0 10 CCH-34 6.0 11 C-BHHO- 7.0 5-04FF Σ 100.0

The liquid-crystal medium has excellent applicational properties, as is evident, for example, in comparison with the following comparative example (CM-2).

Comparative Example CM-2

The mixture shown in the following table, which comprises no compound according to the invention, is prepared and investigated. Composition Com- Conc./% pound Abbre- by # viation wt Physical properties 1 PCH-304FF 9.0 T(N, I) = 96° C. 2 PCH-502FF 5.0 Δn (20° C., 589 0.1127 nm) = 3 CCP-302FF 8.0 Δε (20° C., 1 −3.7 kHz) > 4 CCP-402FF 9.0 k₁ (20° C.) = 16.3 pN 5 BCH-2-02FF 12.0 k₁/k₃ (20° C.) = 0.97 6 BCH-3-02FF 12.0 γ₁ (20° C.) = 179 mPa · s 7 PYP-2-3 9.0 t_(store) (−20° C.) = 950 h 8 PYP-2-4 9.0 V₀ (20° C.) = 2.19 V 9 CC-4-V 13.0 10 CC-3-V1 11.0 11 CCH-35 2.0 Σ 100.0

The liquid-crystal medium has similar values for the clearing point, the birefringence and the dielectric anisotropy to the medium of Example 5. However, it has significantly higher rotational viscosity and at the same time a higher threshold voltage and consequently has less suitable applicational properties. 

1. Compound of the formula I

in which Y is —CO—, —CS—, —CH₂—, —CF₂‘ or —CHF—, L¹ and L² are each, independently of one another, H, F, Cl or —CN,

are each, independently of one another, and, if present more than once, also independently of one another, (a) a trans-1,4-cyclohexylene radical, in which, in addition, one or two non-adjacent CH₂ groups may be replaced by —O— and/or —S—, (b) a 1,4-cyclohexenylene radical, (c) a 1,4-phenylene radical, in which, in addition, one or two non-adjacent CH groups may be replaced by N, or (d) a radical selected from the group consisting of 1,4-bicyclo-[2.2.2]octylene, 1,3-bicyclo[1.1. 1]pentylene, spiro[3.3]heptane-2,4-diyl, piperidine-1,4-diyl, naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2,3,4-tetrahydro-naphthalene-2,6-diyl, R¹ and R² are each, independently of one another, H, halogen, —CN, —SCN, —SF₅, —CF₃, —CHF₂, —CH₂F, —OCF₃, —OCHF₂, or an alkyl group having from 1 to 15 carbon atoms which is monosubstituted by CN or CF₃ or at least monosubstituted by halogen and in which, in addition, one or more CH2 groups may each, independently of one another, be replaced by —O—, —S—, —CH═CH—, —CF═CF—, —CF═CH—, —CH═CF—,

—CO—, —CO—O—, —O—CO— or —O—CO—O— in such a way that neither O nor S atoms are linked directly to one another, Z¹ and Z² are each, independently of one another, a single bond, —CH₂—CH₂—, —CF₂—CF₂—, —CF₂—CH₂—, —CH₂—CF₂—, —CH═CH—, —CF═CF—, —CF═CH—, —CH═CF—, —C≡C—, —COO—, —OCO—, —CH₂O—, —OCH₂—, —CF₂O—, —OCF₂—, or a combination of two of these groups, where no two O atoms are bonded to one another, and n and m are each 0, 1 or 2, where n+m is0, 1, 2or3, with the proviso that, if Y is —CO—, at least one of L¹ and L² is not H.
 2. Compound of the formula I according to claim 1, selected from the group consisting of the compounds of the formulae I-1a to I-3b

in which the parameters are as defined in claim
 1. 3. Compound according to claim 1, characterised in that Y is —CF₂—.
 4. Compound according to claim 1, characterised in that L¹ and L² are both F.
 5. Compound according to claim 1, characterised in that Z¹ and Z² are both a single bond.
 6. Liquid-crystal medium, characterised in that it comprises one or more compounds of the formula I as defined in claim
 1. 7. Liquid-crystal medium, characterised in that it has a nematic phase and comprises one or more compounds of the formula I as defined in claim 1, but in which L¹ and L² can both be H even if Y is —CO—, in contrast to the definition in claim
 1. 8. Liquid-crystal medium according to claim 6, characterised in that it comprises one or more dielectrically negative compound(s) of the formula II

in which R²¹ and R²² are each, independently of one another, as defined for R¹ and R² under the formula I, Z²¹ and Z²² are each, independently of one another, as defined for Z¹ and Z² under the formula I,

are each, independently of one another,

L¹ and L² are both C—F or one of the two is N and the other is C—F, and I is 0 or
 1. 9. Liquid-crystal medium according to claim 6, characterised in that it comprises one or more compound(s) of the formula II-1

in which R²¹ , R²², Z¹² , Z²²,

and I are as defined in formula II.
 10. Use of a liquid-crystal medium according to claim 6 in an electro-optical display.
 11. Electro-optical display containing a liquid-crystal medium according to claim
 6. 12. Display according to claim 11, characterised in that it is a VAN LCD. 